How can I stop this?

I’ve found that with past FWB’s and ONS I’ve often failed to get girls off, and it’s something that eats at me. Maybe I just need more experience, but when I find that when things break down between me and girl im often weighed down by a feeling of regret in my mind that maybe ‘I didn’t fuck her hard enough or long enough or the right way’

Yes I’ve read Daniel roses sex god method, and I’m always trying to implement the methods in that book.

My question is how can I allow myself to relax and stop lamenting over the feeling of past sexual inadequacies? Maybe it’s just my imagination? Maybe its merely a symptom of oneitis?

I’d love to hear your responses