So I recently had unprotected sex with someone who on prep.
He gave me validation he is on prep and takes it daily and he showed my his results which were dated back to 10 August 2018 and he is clean of hiv and stds.
Whilst he has given me lots of reasons to trust him, I am just worried about having unprotected sex (where I was both passive and submissive) and Im not on prep and he is.
He also told me he had sex with 2 other encounters recently who were hiv negative and also on prep...
I just find it hard to trust someone who you dont really know from a bar of soap.
I am not one to be irresponsible and not use protection, so this has been a bit of a mental and emotional roller coaster of worry, and I am contemplating whether I need to just go on pep or not?
The window period ends in 24 hours so Id appreciate the reply so I can go to the clinic if I need to get PEP
PEP ("post-exposure prophylaxis") allows someone HIV negative who may have been exposed to detectable levels of HIV reduce their chances of becoming HIV positive. In the scenario you describe, it seems your chances would be slim to non-existent. Nevertheless, sometimes people take PEP for 28 days simply for peace of mind, then choose to go on PrEP afterward. More on that in a second.
You say you had "unprotected" sex with this person. Yet he is on PrEP and showed you a negative result going back to August 10th. It seems you know him a lot better than a bar of soap. Medically speaking you definitely had "protected" sex with him given he is on PrEP and responsibly got tested regularly. That means he does not have HIV, nor could transmit HIV to others.
However, what I think you're reaching for here is the fact that you cannot trust another person to keep you HIV negative. And on that point, I do agree. You did your due diligence by asking him for that information, but I think your discomfort comes from the fact that you put your HIV status in his control. Yes, he is on PrEP, but anytime you give another person control over your HIV status, especially as a bottom, you will likely feel stress.
Since you enjoy being the passive partner without condoms, perhaps it is time for you to consider PrEP as your primary HIV prevention strategy. PrEP puts YOU in 100% control of your HIV status - so that even if you bottom for someone who turns out to have a detectable level of HIV, you still would have more than 99% protection.
The same person or place that would offer you in PEP in this situation would be able to offer you PrEP as well (given in most parts of the world Truvada is part of a PEP regimen). Depending where you live, you may have to educate your provider about how PrEP helps. For a list of global providers, check out this directory here: https://www.pleaseprepme.global . But keep in mind - ANY provider can prescribe PrEP, they need not be a specialist.
You or and your provider can learn more about PrEP's protection from the World Health Organization here: http://www.who.int/hiv/topics/prep/en/ . You can also discuss PrEP 24/7 with other patients / providers from around the world on my Facebook group page: https://www.facebook.com/groups/PrEPFacts.