Is my molly pregnant?

I can't really tell whether or not my molly is pregnant. I was hoping someone else might be able to tell. Thanks in advance

When I bought her I was told she was pregnant but I haven't seen any change in the size of her belly over the past week and a half.

Did she have had contact with males? If yes, she is most likely to be pregnant and if her belly size hasn't changed then she either has still some days to go or she's tricking to be pregnant.
And I don't know if this is true, but when a female is not interested being pregnant, she just never will be pregnant.
Trust me, I have a female swordtail for several months now and she had contact with males before and she never was pregnant. I think this kind of females will just store the males sperm and never get pregnant actually!
If your female is pregnant, please don't put her in a breeder box as this will stress her out and she is most likely to abort her fry or delay her delivery.
You can put in some live plants, to increase the survival chance of the fry, such as java moss, limnophila sessiliflora, anacharis, hornwort and salvinia.

Thank you. She was in a tank with males at the store so I will make sure to keep plenty of hiding places in my tank.