Diarrhea, nausea, stomach pains, pains in chest, pins & needles, etc

I'm 21 years young & in August 2012 i started with really severe stomach pains, loss of appetite, nausea, bad headaches, constant diarrhea, pains in my chest & the v area of my ribs, (where ribs come together in middle!) in which it makes it difficult to breathe most of the time. I havent been to my doctor as i dont want to bother him if it isnt nothing to worry about! I dont like to waste peoples time. I also had a lump removed out of my neck not so long ago, which has been sent off to hostology, im quite worried about what the results might say & wondered if there was a slight chance they could be linked? Please help if you can, thank you. :)