having pain in my right testicle.

I had unprotected sex 4 weeks ago, and didn't ejaculate. Just a few days ago I started having pain in my right testicle (on a scale of 1-10, with 10 being the highest, it is about a 2). Based on research I did, there's a low chance it's an STD/STI. I do not have any scabs, blisters, bumps, or formations. It does not burn when I urinate. Absolutely no discharge. My testicles aren't tender to touch either, they aren't enlarged (at least from what I can tell), and they aren't warmer than usual. I have no clue what's going on. Please help me. :/