Hello doctor, I did not get an erection that easily and am not able to hold it for long also. I did not last longer than three minutes.
Hi. You need to get yourself evaluated to find the cause of this. If any problem detected, then proceed further accordingly. However, in your age group most common cause is psychological in nature. In such situations, the erectile dysfunction is managed by a drug like Sildenafil or Tadalafil and behavior method called Master and Johnson technique. You can google this technique and can start practicing it.  Regarding premature ejaculation, three minutes is not abnormal per se, and you can increase the time by practicing a few techniques like start-stop technique or squeeze technique or coitus interruption technique. It is quite difficult to explain here but you can google them or can watch video on the internet.