I have mild sensitivity and pain in the left testicle with grade 1 seminoma in the right. Please help.

Hi doctor,

I am a 44-year-old male. Last month, I was diagnosed with stage 1 seminoma in the right testicle and had Rio surgery four weeks ago today. I am beginning adjuvant treatment in the next few weeks. Last week, I experienced symptoms on the left side, and I am curious about what it may be. It can only be described as a mild sensitivity in the testicle and scrotum with occasional jarring ache and can radiate to the flank, hip, and sometimes down hamstring. I experienced this in the past about a year before seminoma diagnosis on the right side, and it lasted about four to six weeks before subsiding. In the discovery of seminoma, all imaging (US and CT, all done in the last four weeks) showed the left one is clean. Likewise, my urologist did a physical exam of the remaining testicle just three weeks ago. Also noteworthy, these new symptoms began a day or two after my partner, and I had sex for the first time post-surgery. Any thoughts on what could be causing these symptoms? Can this be mild epididymitis? I am not worried about something nefarious and have full confidence in my surveillance team. But my next appointment is not until next month, and I am hyper-aware given the recent diagnosis. Please help.