Hard lump under left testicule?

33yo caucasian male, generally healthy. I check my testicules about every month or so for lumps since my vasectomy 2 years ago where I developed a massive scrotal hematoma. The hematoma healed over a few months and has completely resolved by now.

About 2 months ago, I was sent for an ultrasound of my right testicule as I had found what seemed like a relatively firm but small cyst under it. I then had a ultrasound for both testicules which didn’t reveal much - all good. The cyst seemed to have gone away during the wait from urology referral to ultrasound.

Now, about 20 days from that exam, I am discovering what is unmistakably a very hard lump, roughly 1cm diameter and round, embedded in the epididymis tail of the LEFT testicule, so under it. It does not feel attached to the testicule (although it’s hard to tell). It does not cause pain nor do I feel like I would have an infection of any kind. I have been palpating it probably a bit too much and since then I have that mild lingering discomfort of "having been kicked in the balls" radiating around my left pelvis/left hip/left back.

My anxiety has shot up like never before due to how hard this thing is, I’ve never experienced something like it. It also scares me how quickly I went from clear ultrasound to hard mass (20ish days).

While I’m waiting to be seen yet again by my urologist, could anyone here share similar experience and what to expect? Thank you