Female Betta Sick

So a few days ago, my female Betta started acting very weird. she started not eating, and mainly hung out at the bottom of the tank only sometimes gasping for air. She sometimes moves now, and I don't entirely know what to do. I thought that there might have been an ammonia problem hence the water changes and prime.
Tank size: 5 Gal
pH:8.2
ammonia: 0
nitrite:0
nitrate:0-5.0
tank temp:76.6 F

Fish Symptoms:
Fish just sits on bottom of tank sometimes swimming up to get air.
gill slightly open
won't eat
doesn't respond much to stimuli
Volume and Frequency of water changes:
The past two days, I have done 2 one gallon water changes, and today I did a one and half water change.
Chemical Additives or Media in your tank:
I use a sponge filter. gravel
I also added a bunch of prime because I heard that it could stabilize a tank in an emergency.
Tank inhabitants:
betta
Recent additions to your tank (living or decoration):
moved tank three weeks ago because college
Exposure to chemicals:
prime
something that might have been on my hand i don't know