Tingling Scrotum and Pain/Redness in the tip of penis, what is it?

[RobertA22]

I wanted to ask your professional opinion.  For the past 9 years I've had a pain in the tip of my penis, and it gets very red and scaly after any mechanical irritation (sometimes it gets sore and other times just red - it tends to flake off when it is severe.   The redness and shedding occurs quite frequently especially when I am sexually active (can happen several times a month).  There is a tingling in my scrotum as well.  The tingling in the scrotum occurs several times a week, every week.  There are not always visible symptoms of scaly redness since that is brought on from sexual activiy.   I also have a sharp pain in my uerethra from time to time.    

I've seen several doctors, dermatologists, urologists, general practicioners, etc....all with no diagnosis.  I've been told this is possibly dermatitis with no explanation as to why my scrotum would tingle.  I've had my prostate checked and I've been tested for Chlamydia, Syphillis, Gonherria and almost every other std in the book.   My blood test for HSV 2 came back negative, HSV 1 was positive, but I had cold sores as a kid, and I was told that I cannot contract HSV 1 in the genitals if I had the virus orally already.   I cannot figure out what this is and I've had it for 9 years now.  It is really affecting my life.  Have you ever heard of anything with these symptoms (tingling scrotum, redness at tip of penis
and occasional pain in the uerethra - primarily after sexual activity)?