I was porn and masturbation Addicted in past but now I quit it But whenever I go for intercourse or watching erotic movies,I'm not sexually stimulate from inside but precum was releasing and my penis is not getting erect by itself untill I'm rub it My penis is not self erected when I was see any erotic movies sometimes it happen But whenever I go for masturbation my penis is perfectly erected I'm not doing any exercise and workout Does doing exercises and running can cure it How can I cure my problem naturally