Hi I've been really worrying about the possiblity of lymphoma and need help. 
 

3 years ago I went to my gp and got bloods taken as I was feeling tired and just generally ill. I had lumps all round my neck and head, one on the back of my neck one on each side of my neck and 2 behind my ear on one side. I showed these to my doctor and she said they were lymph nodes and not to worry if they went away soon. My results came back and said I had glandular fever so that explained the nodes then. Since then they haven't went away to this day and one is bigger than them all, can't remember if it's grown since found it so long ago. I've also been feeling tired after only a couple hours of being awake but a later blood test said I had low red blood cells so that explained that then. I've found a tiny bump on the back of my head too recently close to the nodes behind my ear. I'm really panicking about them and think it about it constantly as recently I've been getting itches around my neck. The lymph nodes also sometimes have a sharp pain and a rumbling feeling in them  same with my head.I'm only 17 and I'm just wondering if anyone has had a simailr experience or if I should be worrying about this.