Your risk is negligible. If you want to get PEP, you should speak to your doctor because only a qualified professional would be able to assess whether you need it or not.
It is unlikely that your partner is giving out false information about his HIV status and also
it is reassuring to know the fact that he is on PrEP. Right course of action from here is to wait for 28 days and get a IV/V Generation HIV test.
Hi because there was anal intercourse without a condom you did put yourself at risk for HIV. A single antibody HIV test is recommended at the 90 day post exposure.
However, from what you describe it is unlikely that you caught HIV from that single exposure. Try to relax man, you'll be fine.