What is this? (Herpes or pimple)? Picture included.

I had this red spot on the head of my penis for about a week and it has gotten slightly smaller with no irritation or pain at all.

Back story; I had unprotected sex about 4 days ago. A day after I noticed this red spot on the head of my penis and was scared to death... looked all over the web and I don't match any of the symptoms of herpes.. but I'm beginning to think it could be due to how clueless I am about sexual transmitted diseases and their symptoms..

How tf do you post a picture on this

This should help you add images:

https://patient.uservoice.com/knowledgebase/articles/402861-how-do-i-add-an-image-to-my-post

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