Swollen Lymphnodes in neck VERY WORRIED

[KatieR12345]

I am an 18 year old female. I have had swollen Lymphnodes in my neck for maybe a year they are symmetrical I also found two under my jaw which are symmetrical. I'm very worried. I have visited 4/5 doctors and they said it is nothing and that I do not have cancer. A few weeks ago I had shortness of breath and a pain in my right ribs the A&E doctor said it was possibly pleurisy and prescribed me some pain relief and continued to tell me to stop worrying and that I do not have cancer. I have become very itchy and my mind is all over the place. I recently read online that individuals with lymphoma suffer from pleurisy. I also have been sneezing constantly and having itchy eyes. This is concerning me even more, as it could show my immune system is low. I have had a CBC and everything came back normal normal kidney and liver function but despite the doctors telling me I do not have lymphoma I still can't seem to shake the feeling that something is wrong...