Do I have porn induced erectile dysfunction?

Hi, i'm here in hopes for some answers because i'm not sure if I have porn induced erectile dysnfuction. I have been watching porn and masturbating to it from the age of 14 till now (20). I recently got out of a relationship of 2 years and I found that many times, I got hard but then got soft when changing position etc. Even when she gave my blowjobs, it just didn't feel like anything and I didn't get hard. Maintaining an erection was easy once inside but when I pull out to change, I always lost it and it then caused me to develop this anxiety and fear about losing my erection.

However, recently, I slept with a girl and I had no problems maintaining an erection, and I was successfully able to change position, and move around whilst maintaining an erection. What is happening?

tldr had problems with erection with ex but not with a new girl im seeing. What is the problem? sorry for my bad english, it isn't my mother tongue