Why is my stomach so bloated?

2 days ago, my stomach just bloated up like crazy! i haven't drastically changed my diet, with the exception of eating clif bar to increase my calorie intake. And, I did have a small bowl of white pasta once each of these two days, as a bit of a cheat from my usual whole grain only intake. I'm going type 2 just fine (went this morning), so I don't think it's anything to do with that. I think it might be water weight (because I gained a pound in 3 days, while not taking in more than I burned). But, i'm not sure because I drank at least 10 bottles of water yesterday, and i've already drank as much today, and it STILL hasn't gone down! I don't think it's my period either, because that's not due for another week. PLEASE HELP, WHATS WRONG WITH ME?!!?!??!!??!!?!?