Looking for a reality check about a suddenly enlarged testicle.

I am a 43 year old non-smoking man, about 6'2" and 225 lbs. I have diabetes, high cholesterol, and high blood pressure that are all adequately managed by Jardiance, Metformin, Lisinopril, and Atorvastatin. I also take Vyvanse for ADHD.

Yesterday I noticed that one of my testicles is noticeably bigger than it used to be. It doesn't hurt - it does feel a little funny, but I can't tell if that's because something is going on or because I've been prodding it. I have done a self-examination and there are no palpable hard bumps or lumps - it's just bigger.

My uncle (on my mother's side) ultimately died of a cancer that first appeared in his testicles. My father also died relatively young, but his cancer had nothing to do with his testicles (it was a lymphoma).

I've already emailed my doctor, but I'd like to get a sense of how worried I should be. Is this the kind of thing where the less terrible explanations, like a hydrocele or a varicocele or a little infection are more likely? Or is cancer actually pretty likely and I should be prepared for the worst?

Thank you in advance.