What Causes Redness Along With Dry Flaky Skin On The Shaft Of Penis?

Hi about 7 weeks ago I had unprotected sex with a stranger at my bar. the next day my ex girlfriend spent the night and also had unprotected sex. 2 days later my ex had a very red as she described itchy and sore vagina ( both sides of the clit) I had no symtoms of anything until 2 weeks after intercorse with the stranger. About 2 weeks after my symtoms were these Soft almost I describe as red and soggy looking skin under my shaft and at the base of scrotum and shaft. Also the sides of the scrotum and back. This then drys out becomes small flakes and slight skin cracking. On my scrotum only at the base of the shaft. Sore testicals. Sharp pain in urethra, tingling at the tip. I was tested for chlamydia and given doxycline and also flagyl. I finished both prescriptions and felt better. My test results then came back Negetive for chlamydia and ghonnorea. I had an hiv and syphilis test that came up. Negetive, Could this be herpes? The medicine suppressed the symtoms of what ever it is, but then they came back? I m now taking my second tube of Lamisil just to suppress the symtoms! Please help! These are all specific symtoms but my whole genital area is being attacked! Jesse