Hey 21 y/o newbie here

Hi everyone!

I'm a 21 y/o male currently in university. I am doing my undergraduation and will be going abroad for my graduation in another 6 months. I don't remember since I've been watching porn but it has been around the age of 13 if I'm not wrong. After researching and coming on NoFap, I can say I suffer from PIED, desensitisation and PE. To top it all, I overthink a lot and thus have anxiety.

I've met someone and I'm dating her currently. This was 4 months ago. Every time we try having sex, I can't get a complete hard on. I know how big and hard I get, and I've never gotten that big and hard whenever we go at it. She doesn't know that I have PIED and I don't plan on telling this to her either because I want to do this myself. In my last relationship too, I couldn't get fully erect/hard but it was there. Whenever she went down on me or when I went in her (in my previous relationship) I didn't really feel much or feel anything. I ignored those signs thinking that sex might be overrated or that she might not be great at it. I don't want my current PIED to affect my relationship but I feel it will someway or the other. Usually, I start to get flaccid when I'm 90% hard during a blowjob and I don't think I can stay hard during penetrative sex either.

The reason I mentioned I will be going abroad in another 6 months is because I want to make her happy and I want to get a hard on to have sex with her. I understand that she needs to be a part of this too, but I don't think I want her to know this. I know I can do this alone, by myself and do everything needed. That's not a problem.

I've been wondering if a 30-day hard mode will rewire my brain, after which I can hopefully share intimate moments with her which will help me rewire. Will having sex with your girlfriend after the 30-day hard mode help you rewire or will it be considered a relapse? I plan on doing Kegel exercises during the 30 days from today to help with the process.

I need help on what to do, and how to do ASAP. Thank you NoFap community!