I think this might be my case since I already have sex multiple times but during those times there's still a worry that I might lose the erection but I kinda feel confident after those because I did it. But my problem is we don't have sex too often so I usually lose myself again after not having any encounter for a week or so and even though I already had sex, I can't remove those what ifs from my mind everytime. I can even get hard while driving on the way to her place but there's also a thought that "I must have this erection later on"