I can say I am in teh same boat as you. I had sex with my ex girlfriend 2 weeks ago. And the next day I noticed two red marks on my penis, They looked/felt like minor abraisions from the friction, fast forward a week and they have only gotten worse (look infected and bigger and hurt much more). I went to the doctor on Monday and he said it looked like herpes, but it seems almos timpossible Id have it because I have only had sex with my ex girlfriend, and she calims she hasnt had any symptoms and has only had sex with one other guy since we were broken up. So Im am waiting very nervously for my test results to come back this coming monday. Pretty bad feeling. Good luck.
At this point you need to go and see your provider. do not have sex again until things are completely back to normal.
also check to be sure that you were tested for herpes when you had std testing 6 months ago - it's not a part of routine std testing in most clinics. Also talk to your partner and find out if he's had testing or not too.
Do you use lube for sex? also have you tried anything like replens for your dryness issue?
grace