Many things can cause these issues and they may clear up too!
Keep a journal as to what affects u and what else is going on...like stress....IBS....what ever...but do try to find what ur issues r and avoid them to avoid feeling poorly.
http://www.medhelp.org/health_pages/list?cid=236
The above link is for the Health Pages ...please review for tips on diet and lifestyle modifications.....
And as Megan suggested, if u haven't already been seen by a GI dr, that would be the best place to start.
Good luck
"selma"