rash on scrotum

i have had a rash on my scrotum and around the base of my penis for about 2-3 weeks now.  orginally the rash was in my grion area, mostly top of one leg which lasted about 2-3 weeks before that went away.  but during the later part of the groin rash, i noticed some itching and then a very red rash on my scrotum, around base of my penis.  and the skin (sack) of my scrotum seems thick.  when i orginally went to doctor about 3 week ago, i was told it was jock rash, but i am not sure.  also, like to know why, the itching is much much worse at night.  during the daytime, the itch is minimum  but at night the iching is so much more consent and severe, that i have not slept much.  i have been using hydrocortisone cream on it.  but that does not seem to help much.from what i have read, i can't tell if it is jock rash or something other.so any information or help, esp a cure that you can provide me with this problem with be greatful.  thank you