Std while pregnant?

I’m 22 weeks pregnant and I hadn’t had sex with my partner for a while but I did a few days ago and now my labia has been itching a lot.. a shower didnt help and it just hasn’t stopped. I don’t know if this is normal while pregnant. I got tested for stds when I was 12 weeks and I’d like to assume my partner hasn’t gotten with anyone else but he has never had an std test in his life and every time I ask him to, do I can have a peace of mind, he never does it. should I get tested again or is this itching normal for pregnancy? I don’t have weird discharge or smelly or anything but I do seem to have a bit more. thank you