Infection? Allergy? Or just irritation?

Okay so me and my boyfriend have a regular sex life and we’ve used two different Trojan condoms both of which work but the ones we have currently been using I think are causing me to have irritation. They don’t always cause it but occasionally I get vaginal irritation and it hurts to touch or wash down there. I’ve done some research and yes there are plenty of things that could cause this but I’m at a loss because I don’t have any weird discharge I don’t have any cuts or sores or anything of the sort it’s just red and irritated and has been for a few days as I said it happens occasionally but this time it is a much more severe pain and it’s lasted longer. I’m not sure what is causing this because I’ve been sleeping with the same guy for 6 months and we’ve used the same condoms for about 5 of those so if anyone has any ideas or any at home remedies pleaseee help because it’s very very uncomfortable..