Is it possible to get a lil advice please?

Hiya, first of all i am sorry i keep posting and i asure you that i wouldnt be if i wasnt so anxious. It is just that I am 18 and have been of poor health for nearly two years now. It stared when i went out with friends and drank alot and experience nausea on and off after that for months. It got slightly better but i go very tired and still am alot of the time. I recently started getting stabbing pains in my abdomen (both sides) and just under my ribs (both sides but mostly the right) I have had many tests including a endoscopy last year and long behold...nothing. I am waiting for a barium meal xray to come back. It has been 10 days now and because it is the weekend i cant get them now. I am worried sick that it could be colon cancer. I dont have blood in my stools but in the morning as soon as i have eaten i have to go badly and do and my stools arnt pencil thin. i feel sick on and off alot too. Any advice you could offer would be great. Again I am sorry about continuos posting. thank you