I have painful swollen lymph nodes in the back of my neck and a clicking in my throat when i swallow. could they be related and what could cause this?

Nodes: probably not related but you should see an ENT to check it out

Tender lymphnodes: If you have enlarged and tender lymph nodes, it is likely an infection. Since you have not disclosed your age or any medical history we can't provide you with a useful response. I assume you are very young in which case I recooemnd you discuss this with your parents and you will likely need to see a doctor to treat a possible infection. In back of neck, its likely cysts.