How to up regulate my dopamine receptors ?

Hello

I want to up regulate my dopamine receptors.
These last 4 years I noticed that I was getting too much fun and I lost interest in pretty much anything that I liked doing in that period of time.

I was basically playing video games all day, skipping university, and fapping on porn every day 1 time for an average of 2 to 4h.

I noticed 2 to 3 years ago that I was losing interest in video games, I was falling asleep while playing, or I would just stop playing after a few minutes and then wonder what I could do to kill time, there were only 2 options.
I was in a circle and eventually I lost interest in both and I did them by habit.

I am in a different environment now. I moved to another country in which I have work everyday from 9 to 6pm.
Additionally I will go to the gym, bike, meditate and go for a weekly yoga class.
Of I get flexible enough again I will even go back to karate classes.
Obviously, my social life is nowhere close to what I had last month for the last 4 years. But I am still the shy guy who has trouble talking to strangers and who sits alone at the table in bars.

I want to up regulate my dopamine receptors because I feel like I lost joy in what is supposed to make me feel happy.
I am more neutral when people are joking around me, I don't laugh or react as fast as they expect and I look like dreamy, lost in my thoughts.
My main issue is erections, I want them back. I have nightly erections, but during the day I have to touch myself to trigger one. While before, if my mind slipped to thinking about a situation or porn, I would get an erections and going upward 100% firm, not horizontal 50% strong.
I want it back.

I started very recently my no PMO journey and I want advices on how to optimize my dopamine receptors recovery and anything that is relevant in the matter of my troubles aforementioned.

Thank you