I've been keeping track of stuff & i've noticed that after my last 4 periods, i've been experiencing bloating, stomach pain, more frequent bowel movements & nausea after my period has ended; & the symptoms last about a week... any ideas?

Intestinal pain ?'s: The intestinal symptoms noted may come from several sources, most unrelated to immediately after your menses. Women can acquire lactose intolerance more frequently than males, and this can occur in late 20's, early 30's. Lactose intolerance can cause all mentioned symptoms, but primary intestinal disease ("irritable bowel disease") can as well. See your physician if this continues.