Our member has said very clearly you did not have a risk. We wish you well and are closing this thread.
*** Thread Closed ***
So your risk for HIV, chlamydia, gonorrhea, trich, mycoplasma and Hep B are all zero - the head of your penis was covered, and HIV isn't a risk from oral sex.
There is a slight risk for genital herpes type 1, if you don't already have that orally, and syphilis. If she had any oral sores, either from herpes or syphilis, you could get that genitally.
If you have itchy skin everywhere, that's not from any STD or HIV. That could be a reaction to the soap she used, or from anxiety.
Getting herpes from a one-time, protected encounter is very unlikely, and not something I'd worry about. If you notice any genital sores, get checked by your doctor. Don't panic though - your chances are very low.