how much do you need to pee after sex to avoid a uti?

I got a UTI the other week, genuinely didn’t know you could still get one even when using a condom (my ex and i never used one and i got a couple uti’s from that.) I know it’s important to pee after but do you have to pee a full stream or is a little tinkle sufficient? 😭😂 i feel so dumb even asking this. also, how long can you go without peeing after sex? I feel like i never can for at least 15 minutes after having sex.