Good luck. It could be a number of things, but please do see the doctor soon.
And if you (or anyone else reading this) want to chat, get advice on picking a specialist, etc., I'm more than happy to talk - hit me up at [email protected].
A few years ago I got testicular cancer. The information about the disease came in pieces: first all I knew was that there was a lump; then came the ultrasound, the CT scan, then biopsy of the testicle, then a second surgery to sample lymph nodes to which the cancer might have spread. At every step I would obsessively query my doctors for conditional probabilities: given what we'd just found out, what were the chances of dying? Of relapse? Of chemo? Of sterility? I was always incredibly frustrated at how vague their responses would be - they'd say, e.g. "we don't like to give probabilities because you just never know what will happen!". And I would think, "That's exactly the point of a probability! Please just tell me a number!"
One doctor eventually showed me a paper on outcomes for the lymph node surgery I had, with a relapse rate curve going out five years so. I found this incredibly helpful for managing my emotions because it let me track my progress in a very precise way: every monthly checkup that would go by uneventfully, I knew exactly what my chance of relapse had dropped to. The goal was to get to zero. More importantly, having actual numbers gave me something on which I could focus my optimism. It's so much worse to hear "you might become sterile" than "there's a 5% chance of becoming sterile". With the 5% number in mind, I'd do things like imagine myself in a room full of 20 people and think "wow, it would be incredibly unlikely to be randomly chosen from this group". Having spent a lot of time in a cancer hospital now -- around people who were much worse off than I was -- I believe that almost everyone has incredible reserves of optimism. I think it's better when the hopeful possibility is concretely defined - it makes it easier to imagine a path forward while you're stuck waiting for more information.
Mine is obviously a completely different situation from the terminal cancer described by the author, where the question isn't, "when will I be free of this cancer", but rather "when will I die from it". Testicular cancer is very treatable, and I never faced a significant chance of death. I'm sure I would have been in a much different psychological state if I had.
Also, PSA: testicular cancer is REALLY common for young males (if you're male you have a 1 in 500 chance of getting it between 20 and 34). Given HN user demographics, there are almost certainly some of you reading this who've gotten it already, or who will. You can save yourself a ton of trouble if you do a self-examination every once in a while. That's actually how I found out, and is a big reason that I avoided chemotherapy.
And if you (or anyone else reading this) want to chat, get advice on picking a specialist, etc., I'm more than happy to talk - hit me up at [email protected].