I have been feeling really full and bloated?

for the past two or three weeks i have been feeling easily full and really bloated.. i ate one big meal today and i feel so fat and full as if i have been eating all day! but i haven't.. im usually on Birth controll but i wasn't able to get it this month so i think my period is messed up and i haven't had one this month yet.. could that be whats causing all this? would having a period make this stop? i want to know whats going on because im constantly uncomfortable, either im very full or im bloated.. or both.. help!!