Honest opinions

Recently divorced. Only partner was my husband of 10 years, and after him a FWB. It’s been 3 weeks since my FWB and I had sex and he called today asking when I last went to a gynecologist and got checked for STI’s. I told him my last checkup was 2 years ago when I had my son, but I’ve only been with him and my ex. I have no symptoms at all of an STI and haven’t, but he told me today one of his testicles is swollen, it burns when he urinates and he feels the urge to go often but can’t get much out when he does. He claims he hasn’t been with anyone since me, but I’m not sure.

Like I said, I don’t have symptoms and it’s been 3 weeks since we had sex. I’m thinking he has a UTI or got it from some other chick. Thoughts?