MeierEce,
I can certainly understand your anxiety and I am with Rosie on this one. If you need peace of mind, go to an expert and put this thing to bed before it destroys you. In my case, I had no symptoms or reason to go to the doctor other than a lump under my chin that eventually grew to the size of my thumb. I could see it in the mirror. I went to 4 different doctors for 7 months because I could barely turn my head in one direction. I chose the wrong doctors and just wasted my time and theirs. Finally, I went to a plastic surgeon because of the knowledge they typically have with all the nerves in the face and neck. I asked him to remove the nuisance from my neck. He wanted me to see an ENT for a workup for a second opinion. After going almost monthly to doctors I chose to just have it taken out. My wife was with me and had a hard knot on her neck to so we scheduled mine in the hospital and hers in the office. After surgery the doctor felt I had some type of bacterial infection in the lymph node and suggested the puss-filled gland was tuberculosis. On the following Monday it came back as metastatic Squamous Cell Carcinoma. I then had more tests and it clearly showed up on the tests. I even went back to a panoramic xray from the dentist and could see the cancer that my dentist didn't notice. I covered it with his staff as well in case it comes up in the future.
My point in all this is that I had no symptoms and eventually had a piece of the lump available for biopsy and then there is no question. Going repeatedly to doctors who have to guess is not your answer and based on the tests they have performed, I would imagine they would have found something by now. Get a biopsy of the lump and get on with the rest of your life. I can sense from your post that you are not convinced and even CT scans, MRI's, etc., will not give a 100% diagnosis. The lump is bothering you, get it checked. End of story (I hope).
In the meantime, do not waste all your waking moments worrying about what isn't. Even if you turn out positive with cancer, you have wasted an inordinate amount of your time. Your fears will only propagate more paranoia and more things to worry about. Spend time enjoying this new life you and your wife are bringing into this world. There are so many fascinating things surrounding creation and birth of a child and you may be missing out.
I believe any moment of any day I can concentrate really hard and realize my throat or neck hurts to some degree. I prefer to fill my time with other things so I don't notice it or I would be a basket case. Fill your thoughts with positive things and stop thinking about the lump all the time.
Just a few suggestions and lots of free advice!
Ed