Anal Rash

Thank You for taking the time to read and answer my question. Any response is greatly appreciated.

I am a 21 year old Female, of reasonably average health.
Around the 9 of August, I had vaginal intercourse with a close friend of mine, & wore protection.
The next day, I started my period.
About 5 days later, as I was ending my period, I started to get a furious and intense itching around my anus.
Assuming it was caused by my liner or underwear, I dismissed the itching.

A few days later, it started once again, and this time I took a look to see if I could get a better idea of what it was.
What I saw, made me freak. It was a giant, bright red/pink, bumpy rash.
I tried to clear it up by applying BUTT PASTE diaper rash cream.

I've had the rash for a month now, and it hasn't gotten any better.

At times after having made a bowel movement, I will find blood in my stool and some soreness in my lower abdomen.


Any ideas on what could have or might be causing this?

Any information would be greatly appreciated.

Thank you!