Std help. I’m scared.

I’m male, 34, no history of stds. I've been having unprotected sex with strangers for the past few months, and a couple days ago I noticed during unprotected sex a burning sensation. it felt like it was dry but I kept going. the next day I noticed an irritation on my penis but thought it was from friction. The next day I noticed a red mark on my shaft and two smaller white marks above it. I thought it was just friction but I’m nervous now it could be herpes or something else? it has been 4 days now and it doesnt seem to be getting better. What do you think? I won’t be able to see a doctor for a week since I’m traveling. Any thoughts and help appreciated. Thanks, Joe

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