Suggest Treatment For Persistent Stomach Pain And Bowel Movements

Hello I have been having problems with my tummy for the past year now in and out of the hospital and doctor office, They been taking blood samples for everything they can do in the er, Now my doctor took blood also had me take xrays Ultrol sound like and much more even had to lay under a table for few hours for pics\video.. They can not find nothing at all the problem was that every time i ate something in a few min to seconds my tummy would hurt so bad be to painful to explain the pains but also always ran back fourth to the bathroom. Now it s been a year since the pain has stopped but now ever time i eat or drink something I am always have to rush to the bathroom then my tummy would hurt after that going back fourth off and on can stop at times. I haven t let my house in few month because of how bad the pain is even when my tummy feels fine i go out with my grandma to the store for food or what not and i cant even sit in the car for 2 min without going to the bathroom so bad. There is no blood when i use the bathroom i can eat anything and this happens were i can t stop going to the bathroom to were i can t even sleep my doctor can not find nothing at all can you please please help me find out what this is! I am a female age 20 I weight maybe about 339 but I don t look like it at all.