I have had a similar problem for the past year. When it started I realised that I had had this condition before - when I was 10 and again in my twenties - I am now in my forties - it was always when I had a cold and my immune system was run down.
I have experienced pain in my anal region, tingling on my scrotum, reddened scrotal skin and terrible itching. It has been difficult to walk, sit or do any physical exercise. My life has been a living hell!!!
I have tried everything to cure it and spent a great deal of time searching the web for solutions.
HOWEVER, THE GOOD NEWS IS IT'S GONE!!!!
Here's what I found out - it's caused by bacteria that shouldn't be where they are (!) - and the cure for me has been to apply VINEGAR - these bugs don't like acid and what we all tend to do is apply alkaline based solutions to the affected area - making the condition worse!
I have applied approx 3 tablespoons of vinegar mixed with 6 tablespoons of water to the affected area - I had relief from the tingling in a matter of 3 hours and all the pain went within 6 hours.
I have been pain and discomfort free for three days now.
Try it - what do you have to lose apart from the pain
Good luck!
I can't tell you what's causing it - only a doctor could - but it could be an allergy, irritation, a fungal infection, etc.
You should see your doctor.
Aj