Help with Stomach pain?

Ever since I at Chinese food at Chinatown(I know I probably shouldn't have eaten it) I've been ridiculously gasey and have had stomach pains, at first it looked like I had diarrhea but it wasn't super dark green, it was like a yellowish brown thing going on. But that went away after I took medicine and I don't feel super gasey anymore.Anyways I've been getting this stomach pain mainly in the stomach area and it hurts, it doesn't exactly feel like stabbing pain but like a weird feeling like that sick feeling you get sorta but not exactly.It's kinda hard to describe it just doesn't feel good and it feels very uncomfortable. I don't feel like I need to barf but it hurts pretty bad in my stomach and immodium helped for the diarrhea and pepto bismol helped earlier in the day for my stomach but after I don't know how many hours I have it back again. Though the pain was not as painful as it once was. Do you know what it could be? I also have been trying to drink more water and that usually relieves some of my stomach pain and it usually hurts after I ate something like Ravioli and a bit of grilled cheese. when I ate a banana I felt okay.