Hi,
I just read your post. It’s very unlikely that your stomach would be getting larger after not even a month, its probably you just being paranoid. Just relax, dont go around telling anyone just yet, and if you are late for your period by 3 -7 days do some home tests and even go to the doctors to do a test there. You are most likely not pregnant, but check anyway. Dont panic so much, it wont do you any good.
Good luck