alot of swollen lymph nodes/ back pain. Help!

Im a 20 year old male .About a month ago I had a lymph node pop up on the back of my neck (right side) , and about 2 days later another came up below that one, the next day another popped up on the other side of my neck , then the day after that one came up on my left cheek. That was all that came for awhile but about 2 days after that one came up I got one on the front right side of my neck. The next day one popped up on the left side above my collar bone. That is when i really became concerned because thats the one I heard you needed to worry about as far as cancer goes . They only hurt whenever they first popped up and after about a day after each popped up they didnt really hurt. While this was going on i had been going to the doctor on and off since the first one had popped up , at first they werent too concerned but by now i have been through many tests, They tested my blood for about everything you could think of (white blood count , liver , mono ...and so on) everything came out negative. I also had upper chest X-ray done ,again negative. Then I went and had an abdominal CT done ...also negative. Well its been about a week since that and my lymph nodes are a little smaller than they were when they first came up but are all still there. The first one that came up actually went completely away for a few days but has come back up. Ive also been having some occassional stiff neck , abdominal pain , and alot of lower/mid  back pain. Im just still really worried and want to know if i should have anything else to worry about now? Is there anything else i should have done? also I have no weight loss or energy loss or anything like that. I have a weird swelled area in the middle of the back of my neck ,its not big or painful , you cant even see it but i can feel it. Also just today it feels like two new lymph nodes are swelling up almost in the middle of my neck one right above the other. It feels like my tonsals are swollen too. Ugh this is so scary and frustrating i dont know what to do. Last i went to the doctor he seemed almost positive it was just viral but that was before all this back pain and the 2 new lymph nodes! I have no family history of any cancer at all. I keep thinking it could be lymphoma or thyroid cancer or colon cancer or something ....i looked up so many things and it just seems like so many possibilities! Help asap please! thank you!