You have posted on the wrong forum. I will briefly answer your question but if you have additional questions any further questions, they must be on the HIV forum. Sorry, those are the rules.
The risk associated with this exposure, despite the fact that your partner was high risk, is rather low. Chances are that your partner was not HIV infected. Even if she was, your risk for HIV is no greater than 1 in 100 and probably far lower (there are no average figures for HIV risk related to sex with a person who has undergone sex change surgery). However, I can understand however that you would like to get tested. To get an HIV PCR at this time will give you no useful information. Instead, I woud suggest you get a dual, antigen/antibody test at 4-6 weeks following exposure with a follow-up test at about 8 weeks Your 4 week result will identify over 90% of infections acquired 4 weeks earlier while the 8 week test will give you results that you can be completely comfortable with.
I hope these comments help. Take care. EWH