I was 19 when I went through the hardest part of my porn addiction. I quit porn when I couldn’t get it up with a girl that I liked a lot, she started crying, I felt terrible. Effectively ruined my chances with one of the coolest girls I have ever met. That was all the motivation I needed. I have had relapses since then, but it will never get to the point it got to.
You just have more energy, and will power for that matter. I feel like I make better decisions when I don’t jack off. It’s like I’m more comfortable in my skin, and I don’t need things like alcohol or fast food to feel good, but the worst depression I ever experienced was also during those periods, porn numbs your feelings, so when you finally have to deal with them it can be pretty fucking difficult. As for how long it took, I would say around a month and I was getting boner in class like fucking middle school again. Hope that satisfies you.
I don’t know much about performance anxiety, but I do know that PIED made me very anxious about how I was going to perform. And though ensnared by porn usage at the moment, in my periods of prolonged absence from porn I definitely was not anxious about how I was going to perform. When you are that fucking horny the last thing I cared about was if I was going to get it up. So in my experience there was a causal relationship between performance anxiety and PIED, and it definitely stemmed from PIED.