Blemish on head of penis. Very concerned. Please help [nsfw]

About 31 days ago, a girl who had HSV2 kissed my ear and neck. This uncomfortable dot showed up about a week ago (3weeks since). I'm very concerned but have seemed to give myself anxiety hypochondria. Hoping this is the same kind of thing.

I'm male, mid twenties. Any help is greatly appreciated. Picture for the brave [nsfw]: http://imgur.com/8os5Dpy

Hoping ie said enough here. Feel free to inquire about anything.