I've been feeling not quite right for a few years now.

I'm 20 years old I've been experiencing  bone/joint pain since I was a child with no swelling. Dr's have said it's not arthritis. I also have had lots of infections mainly UTIs since I was 12, which would come out of the blue and not because of sexual activity. Since 2 years ago I've been having trouble with eating and experience nausea and since January (7 months ago) I have been vomiting either daily or every other day. I sometimes feel like the lymph nodes in my neck are swollen and they are tender to touch when there is no sign of infection, they flare up every month or so. I also experience this pain after drinking alcohol and feel very ill very quickly. I also experience lymph node swelling occasionally in my armpits, again without infection. I constantly feel warm and have to have a fan on me at home most of the time and I'm usually uncomfortably warm of a night time, but especially so whilst I am out and about or at work. I have become more and more fatigued over the last 2 years and I become exhausted now by simple activities and going outside. I've been for a blood test and apparently everything was fine. The Dr's haven't mentioned cancer or any tests and I really feel like it should be ruled out before they diagnose me with what they have suggested, fibro or ME. I've been going to them about my symptoms for a while now and it seems like I'm starting to make up everything that's going on or I'll never find the cause. 

Does anybody have any advice or suggestions. How should I go about this to the doctor? Are my symptoms possibly cancer related or something else? Any help is much appreciated

Best wishes Niamh