Bloating?

Is there reasons why my bloating is so excessive? I’ve been asked so many time “are you pregnant?” “Are you sure you’re not pregnant?” My gyno said bc would help and was basically trying to force it on me but I dont want birth control cause I actually want a baby

. I’m currently on my period but my stomach looks like this all the time maybe not as big but definitely the same. I am a very slim person and it used to be flat so it looks weird. This is my stomach relaxed, im not pushing it out or anything.