Early erection issues

I’m 18. When I was 17 I started I had a teen circumcision because my foreskin was so long I couldn’t pull it back.

A few months later, I lost my virginity with my first partner and things were going great, the first time it took a second to get it up but that was just nerves.

A few months into the relationship I stopped playing my lifelong sport, which is where all my cardiovascular exercise was.

By the end of the relationship, I had a few moments here and there were I struggled with firmness in my erections.

Now having broken up, I struggle to get hard for myself and don’t always wake up with a morning erection.

Last 2-3 weeks I’ve limited masturbation (only done it once). I’ve been going to the gym daily, eating better food, and completely stopped watching porn.

I fear though, that I’ve only seen very minor improvements in this time. Am I expecting too much too soon? Or is there specific things others would recommend doing?