Dear www.ali143sha, IN your thirties you are in your sexual peak why so stressed, stress, scotch sugar, and smoke , are major factors for ED. If any of them you are having avoid it, try to enjoy preliminaries , don't just rush for penetrative sex , better consult sex counsellor. Masturbation
has nothing to do with this problem, don't have guilt feeling in this regard.good luck you will be enjoying sex in few days. if properly counselled.