Correction: [Before she tried to penetrate with a condom, I applied lube and pushed in, stupidly enough adding risk as I might had pushed precum inside my rectum.]
You do not need pep from what it sounds like. First, pep is a pretty hard medication to tolerate. Loads of rough side effects and this is why they reserve it for situations of say, your having unprotected sex with someone that is KNOWN to have HIV. This person uses condoms which is a good sign they protect themselves.
The only risks for HIV are to have unprotected vaginal or anal intercourse or share IV needles for drug injection. Penetration is required for the unprotected vaginal or anal. This does not mean pressing against even firmly. It means all the way in. You'd know it, you'd feel it and it's not a 'maybe' situation. did this happen?
Otherwise, frottage or rubbing penis against your rectum is NOT risk. Giving oral sex or receiving oral sex is NOT a risk. Air and saliva inactivate the virus.
The advice was clear there are only 3 risks, so there is nothing else that can be "understand your... "
Your situation involves personal contact with an object in air (frotting, penis, etc. ). You will be happy to learn that you had no risk, because you can't get hiv from personal contact except unprotected penetrating vaginal or anal with a penis, neither of which you did and you didn't share hollow needles to inject with which is the only other way to acquire hiv - there are only 3 ways to get hiv. Analysis of large numbers of infected people over the 40 years of hiv history has proven that people don't get hiv in the way you are worried is a risk.
HIV is a fragile virus in air or saliva and is effectively instantly dead in either air or saliva so the WORST that could happen is dead virus rubbed you, and obviously anything which is dead cannot live again so you are good. Blood and cuts would not be relevant in your situation since the hiv has become effectively dead, so you don't have to worry about them to be sure that you are safe.
There is no reason for a person to test when they are safe. The advice took into consideration that the other person might be positive, so move on and enjoy life instead of thinking about this non-event. hiv prevention is straightforward since there are only 3 ways you can become infected, so next time you wonder if you had a risk, ask yourself this QUESTION. "Did I do any of the 3?" Then after you say "No, I didn't" you will know that it's time to move on back to your happy life.
No one got hiv from what you did during 40 years of hiv history and no one will get it in the next 40 years of your life either. You can do what you did any time and be safe.