For background, I am a 25 year old female, no history of any physical medical issues. I do have depression, anxiety and OCD.

For about 3 weeks now I've had some swelling on the right side of my neck (no lump just swollen) and a full feeling in my right ear and below my ear near my jawbone. Its not really painful, just uncomfortable because its swollen and feels weird. Sometimes it feels a bit warm there too but im not sure if I'm imagining it. I've also been having dizzy spells every few days and I have had one occasion where I've heard a loud static sound when I'm feeling dizzy and faint. I've not really got a sore throat, cough or runny nose. I have slight pain when I swallow on the right side of my neck/ear but only sometimes. 

I've been to my GP 3 times, twice been turned away by them saying it will clear up as its just an infection but irs not going away. I had an appt this morning and finally got them to book me a face to face appointment so they can examine the swelling and look in my ear. 

Due to my OCD and anxiety I have become completed obsessed with the idea that I could have lymphoma or another type of cancer and I am absolutely terrified. I cant eat, sleep, or function. All I can think about is finding out I have cancer and what that would mean. I've mentioned this to my GP who just told me "not to stress" but its not that easy for me.

I think I'm just here looking for some reassurance, im not really sure. I also wondered if anybody could help me with what I should ask for at the GP office tomorrow. Should I request blood tests too? Would blood tests show signs of cancer in my body?  How do I get them to take me seriously? 

Thank you!