Penis has redness / rash a few days after sex

hi, i stupidly had a one night stand 6 days ago unprotected and i have been overthinking an std / sti since. i have noticed a red rash under my penis tip and on foreskin. i have been washing a lot more to clean it due to being paranoid and it may be irritation but i would like more opinions. i am going to a GP asap but cant for the next few days due to christmas. anyone have anything similar or can help possibly identify the issue?[](https://)

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