CT shows lymph nodes from infection, bloodwork shows no infection. Is it lymphoma?

[veryconfused89]

For the past few months I've had tiny hive bumps that I believe are cholinergic urticaria caused by fevers. For the past 3 months I've had almost daily fevers ranging from 100-101.5, usually staying around 100.6. I've had a lump on my left neck, just below the mastoid bone, that has been growing and hardening for years. It can be felt when I touch it and my husband can feel it also. My PCP felt it once, but couldn't feel it the second time (I could feel it still, I think she was feeling too low down but I didn't push the matter). In early February, I was sick with a bad case of walking pneumonia that took two rounds of antibiotics to get rid of. I went to my PCP about the chronic symptoms in early March. Extensive lab work came back normal with the exception of a positive ANA test. I was sent to rheumatology, more lab work said I don't have an autoimmune disease, a second ANA test came back positive. All other labs are normal. Infectious diseases said I don't have an active infection and sent me to hematology/oncology. An ultrasound of the one spot on my neck failed to show any signs of enlarged lymph nodes. Again, I think they were too low down. Normal abdominal ultrasound. A CT scan came back this morning showing mild prominence of bilateral tonsils consistent with an inflammatory process and diffuse cervical nodes which are within normal size range and appearance compatible with reactive nodes.

My understanding is this - the CT scan says I have slightly enlarged lymph nodes/tonsils, but they're from a recent infection (I haven't been sick at all since early February). Blood work said I don't have an active infection.
I do have fevers, itchy skin, hives that look like cholinergic urticaria, random profuse sweating episodes that soak multiple shirts (though this hasn't yet been at night), continuing fevers, and extreme fatigue. Could this be lymphoma? How can a CT say I have signs of an infection when my blood work says I don't?
I had an MRI of my jaw due to stage 2 TMD in early December. The MRI also shows my neck in some slides. My doctor won't compare the MRI to the recent CT to see if the nodes are visible in the December MRI.

I've had scans come back clear for other conditions (full shoulder surgery, appendectomy, etc) until it was too late and eventually required surgery. I'm terrified that's whats happening now. I'm at a loss.

[Tippy_Lew]

Hi I'm sorry your not feeling well.  This made me think of when I was a teenager I was sick and admitted for fever and tachycardia. I had those little bumps all over my neck. They told my parents they were swollen lymph nodes from the infection I had.  Have they tried any kind of medications ?  This also  sounds a lot like lupus as well and with a positive ANA you may want to ask your dr about it  Hope you feel better!