Bad pain & diarrhea
If you haven't had much to eat for several days, & you have what sounds like severe pain when you eat you should really be evaluated by a physician without delay.
At the very least you are at risk of dehydration
. Six days of persistent symptoms is worrisome for significant infection, inflammation
of the gut or even a disease state elsewhere in the abdomen. Don't try to sit this one out!
Answer assisted by Mike Moore, Medical Student