As your question has been fully answered, we are now closing this thread.
*** thread closed ***
Are you having any symptoms?
Oral sex and frottage is much lower risk than vaginal or anal sex. It is not considered a risk for HIV, and your test at 29 days is conclusive, so you do not have HIV from the encounter.
20 seconds of oral sex is probably not going to result in transmission of anything, nor is frottage, but if you are worried, why not just test for STDs and put your mind at ease?