What Is The Treatment For Erectile Dysfunction?

Hi my self Vishal I am 22 years old I m not married I am still working I am a well built man with a great personality with 6 ft height but I have a small penis its 2.cm in normal and 3.5cm when erect when I am having sex I am unsatisfied while having sex before give up its get normal and after 2 min its get erect
Again and we r getting unsatisfied plz give me some solution I don't want spoil my life after Two year I wanna get married also plz help me