Blister type thing on bum cheek

I had unprotected sex 11 days ago and have a solitary lump/blister on my bum cheek. It is only slightly raised but still looks like it has some shallow fluid inside I am worried that it could be herpes or warts. Anyone had this before or know what it looks like? I know i shouldnt have but I stabbed into it with tweezers and it didnt really 'ooze' out like i expected. When I squeeze it now, clear fluid comes out still. I have attached photos of before I stabbed it and one of how it looks now.

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based on what your saying about the clear fluid i would go have it swabbed to rule out herpes, does it burn? are you having any other symptoms. i think its most likely a infected pimple.

Only burns when i touch it but it didnt before i stabbed it with a tweezer haha

haha im a picker too! its more than likely a pimple try not to mess with it lol