Black marks Itchy and Burn in between my leg and scrotum?

i first felt this problem in last October last year since i starting working out and sudden at night i feel extremely itching around  both sides of my upper leg between my scrotum almost every night sometimes i even awake up and noticed my hand was inside my pants on the itchy spot so it seems even i was sleeping my body is scratching the itchy spot , few weeks later i noticed that there's a Black markings around my scrotum i though it was a ordinary jock-itch so i brought some cream and powder remedy for jock-itch i treated it however the black spots is still there and it only starting to itch when i touch the those spots or if my underwear rub to these spots , im planning for going to Doctor but i was scared and shy and by the way im 23 year old male and a virgin ..so any advices?