Thank you very much for your post and welcome to our forum.
Firstly I would like to say that your sexual encounter can be considered low risk from the poitn of HIV infection: uknown status of the lady, condom breaking, and short exposure. Let me answer each of your questions here below:
A) No, it is not consistent with acute sero-conversion as symptoms started far too early. The rash would only occur after at least 2 weeks form the exposure, together with a high temeprature and a severe sore throat.
B) The rash is located mainly in trunk and arms. It does not itch.
C) It is maculo-papular, like many other viral rashes.
as a further point to the above..the itch on the neck was more like 5 - 7 spots rather then an all out rash..