I recently had an exposure at an asian massage parlor that included protected vaginal penetrative intercourse. After ejaculating inside the condom, she proceeded to remove the condom from my penis using a tissue paper. After touching the outside of the condom that is wet with her vaginal fluid, she immediately used it to wipe my penis, coming into direct contact with the opening of my penis. What are my risks and the probability that I may have contracted STI from this exposure? Thank you

Welcome to the Forum and thanks for your question.  Congratulations as well on your commitment to safe, condom-protected sex - it will keep you healthy.  STIs are not transmitted through transfer of genital secretions from person-to-person, whether they are on a person's hands or on the surface of a tissue.  The immediately become non-infectious on exposure to the environment.  It is for this reason that even relatively conservative organizations such as the CDC state without equivocation that mutual masturbation, even when partners get each others genital secretions on one another is safe, no risk sex.  Even if your partner had an STI of any sort (it is statistically unlikely- most CSWs do not have STIs), the events you describe would be no risk.  There is no reason for concern, no reason for testing.  

I hope that this reply is helpful to you.  EWH