My turtle has problems...

[Red15]

Hello forum. So I brought this Indian roofed turtle home about 5 days ago, it's somewhere close to 4 inches, probably a female and currently has a 40 gallon tank to live in.
She was quite an unexpected welcome for me and while at the store her shell was wet and it was hard to notice the thin flaking patches on it that I can see now. There's no fluid discharge from her body, eyes are clear. But she hasn't been eating since I've brought her. I've tried pellets, shrimp, mango, papaya, even fry of guppy-she thinks of me as a threat everytime I'm near and opens her mouth like she wants to bite me. Only in the morning does she stay in the water for 1-2 hours then she won't go back there until next morning. Sometimes she just floats in the water but she can stay under water for long and doesn't gasp or breath open mouthed.
The day before yesterday I noticed the dark patch on her throat and it's really worrying me.
I've watched on a video that sunlight can help bacterial infections, and I haven't yet got any UV lights. So I put her on the sunlight for 2 hours everyday on my balcony. As far as I can see, she likes the warmth of hot summer sun, hanging out doing nothing but spreading her legs like a flying bird and sometimes wandering around occasionally.
I know something is wrong with her. Is it shell rot? Infection? Why is her shell flaking off? Please help me!
Here are some of her pictures:

 

[FishNturt808]

It’s good you gave her some sunlight to bask in. If you can’t keep some of it on her tank, get a UV light as soon as you can. Turtles usually need a good swimming space and something to haul out of the water to bask on under their uv light. Most turtles need it for shell health. They also tend to need a calcium supplement. When I had a red ear slider I would give him the cuttlebone floats (I think zoo med made them). Are those spots on her belly soft? If I remember right that’s a sign it’s shell rot. Uncle google is gonna be a valuable resource. Make sure you read numerous sources. There could be a issue with your water if she doesn’t want to go in it. Get a test kit (api master kit is most used and recommended), find out what parameters is recommended for that species of turtle, and go from there.

 

[GaryE]

While you wait for someone who knows more about the species to contribute, I'll bump this one up, but also say my red eared sliders would lose plaques off their shells as they grew. It was a harmless, occasionally filter blocking process.
I don't like those belly marks, but I have no familiarity with those turtles, either.

 

[Herpin Man]

The carapace photo appears to show normal shedding of scutes. The pits in the plastron appear to be a moderate case of shell rot. It’s a bacterial infection caused by being kept in filthy water and/or not having an opportunity to dry off completely. Although I can’t be sure from the photo, there may be minor shell rot on the carapace as well.
Although I don’t want to discourage you from seeking veterinary care, this is not difficult to treat yourself. First, scrape the yellowish matter from the pits in the shell, and allow the turtle to completely dry off. Then, apply betadine, followed by silver sulfadiazine. Keep the turtle dry for several hours. Repeat twice weekly for a month.
The turtle should have clean water, heat, and filtration, a basking area that allows it to dry off completely, a warm basking light, and a UVB light.
Are you in the U.S.? Pangshura are very uncommon here.

 

[Red15]

She isn't still eating, I keep trying though-she's gotten so thin in a week. But she walks around all day like she's exploring, never daring to pass through the door of my bedroom, only watching from a distance what's going on outside. Last night, she's slept under my bed. I let her out after evening because I hadn't been home all afternoon for her beauty walk-i couldn't get her to get out from under my bed-she is so stubborn, and I didn't want to disturb her thinking she liked the darkness, since my studies keep the light of my room on for long into the night.
so I put some water before her and let her be. When I woke up next, I found her out of my room for the first time.
She's so adorable. And these days, when I let her bask in the sun, I can see that she's gathered enough bravery to move away from where I put her.
Pretty sure she hates me though for trying to feed her.
The dark skin on her throat looks like it's peeling, and she has nasal discharge after coming up from the water. Can turtles have runny nose?
Her eyes look a bit cloudy today.
She's really panicking me.
And nope I'm not in the U.S., I'm Asian, pangshura is the commonest here.

 

[Red15]

Now she has blood on one of her nostrils. What do i do about her? I can't even make her eat to at least give her nutritions to fight problems internally. Can you force feed a turtle?

 

[Red15]

Alright, she's in the water and i can see she's shedding skin-a lot of it. Mostly white skin hanging off her legs and face, also the striped skin of her throat too.
Is this normal?
The drop of blood on her nose is gone, I've tried to feed her egg yolk(boiled) softening it with a bit of water, but she has spitted out the watery mixture I've tried to feed with a syringe(yes, i've been careful) but most probably has eaten a bit of dry yolk i've given her.
The cloudiness on her eyes seems to be going away, then coming back. Right now, her eyes are lucid enough.
I'm thinking of giving her ciprofloxin bath for 10 minutes, can i do that?

 

[Herpin Man]

First of all, the turtle should be in a proper enclosure- always- and not free roaming in the house. It also sounds like the turtle has a respiratory issue, and needs to be seen by a vet. It probably needs antibiotics. It isn't eating because it isn't being kept properly, and/or is ill.
I think you should research proper care of this species, or it isn't going to survive.