25 weeks & my stomach feels awful

I'm 25 weeks pregnant and ever since the weekend has past for the fourth. I've been having pain in my stomach. Everytime I eat I have diarrhea. My pains mostly feel like pain when you have diarrhea. The pooping has stopped but I'm still feeling pains. Btw I ate too much work on the weekend could it be from the greasy food? But I has been like 5 days already. Anybody else feel like this during last 2nd trimester.