If it's your vulva that stings, you may have a tiny cut or abrasion ... that should heal on it's own, if you leave it alone for a few days.
If it's your urethra ... Keep a close eye on it. Sometimes i just get a bit of irritation after sex, and the first time i pee stings, but it's fine after that. If it continues after the first few times you pee, you may already have a UTI.
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