Diarrhea and IBS

I'm wondering if diarrhea or constipation is more frequent with IBS. It seems that most people seem to complain about constipation but my problem seems to be diarrhea. My IBS seems to manifest itself more with diarrhea shortly after eating. it's better if I'm VERY careful of my diet...eating very bland foods, so I'm now wondering if maybe I have gall bladder disease or an ulcer. I won't have insurance for another month so no doc right now and just wondering what's the best way to treat this. i thought the Zantac i was taking was causing this side effect but I haven't taken it in a couple of days and it's still the same. I also suffer from health anxiety so wonder if that's affecting me because the more I worry, the more frequently I get the diarrhea.

Thanks Ides, I've been starting to do that but for the first time I can understand why all these ads on TV about Chrones/Colitis/IBS show people anxiously making sure a bathroom was close by....and the more you worry about it, as you say, the worse it is.