Took PEP even if it is low risk.
So, you had a risk but low as has been said. Really low. Testing is something you should do but I would not go the route of PEP if I were you. And going to the ER to get it is unnecessary. If a doctor has already said it is not necessary, go with that rather than putting yourself needlessly through the discomfort of PEP (hard rug to take). Testing needs to happen only one time, at 4 weeks (28 days or more) with a 4th generation Duo test. If you can get that test and it's negative at 28 plus days, you're good. And as anxiousnomore says you can always also ask the guy if he has recently tested or to test. But overall, you have a short time to wait for your answer and I'd bet my pinky finger you are completely negative.
i forgot the source: https://www.cdc.gov/hiv/risk/estimates/riskbehaviors.html
The chance of getting HIV in receptive vaginal sex is 8 out of 10,000 statistically speaking. So the risk is there... but not very high, as they told you at planned parenthood. If the exposure was yesterday, perhaps you can try again at an emergency room of a hospital to get PEP. but i don't think they'll recommended either, unless you were certain of an HIV+ status. or if he were from a high risk population (MSM).
Anyway.. you should get tested with a 4th GEN duo test (p24 and antibodies), at 4,6, and finally 12 weeks (for reassurance). If you came sick between this time.. don't stress about it.. HIV cannot be diagnosed through symptoms. so anything you can gooogle about will seem like ARS.. and you might get paranoid.. so dont bother. just endure and wait until de 4th week, when you will have a test with 95% accuracy. i really wish you the best of luck... and always remember.. to be safe before sex.