I don’t last as long as i used to any idea why maybe?

I am not new to sex and know how to please my partner very well..lets go back to the beginning i always used to masturbate alot and i mean alot maybe 3 to 4 times a day and used to watch alot of porn even when me and my wife where together..but recently i stopped watching porn and masturbating..now when we first met i used to last a long time..to be honest i struggled to ejaculate and suddenly now that i stopped watching porn and masterbation i barley last 2 minutes i don't know if my brain is starting fix itself eg..dopamine,seratonin stabilization or what..it isn't impacting our relationship since i still make her orgasm before i do..but its very confusing cause i lasted hours no i last zero..do you think its cause i stopped watching porn?