Thank you for your query at DoctorSpring.com.
I have gone through your details and I can understand what you are going through.
The condition that you are suffering is called premature ejaculation. Now its a type of anxiety disorder and the person normally suffers from performance anxiety where in he is anxious if he can perform or not.
The best part is with time this problem settles down on its own. Ones you are married and perform sex in a legally and socially accepted relationship there are no doubts in the brain and that leads to proper sexual act.
As of now you can try the start stop technique. Your girlfriend is supposed to start stimulating you and the moment you are about to ejaculated she is supposed to stop all the stimulaton and and hold your penis head hard.
Perineal exercises also help. These are the muscle exercises that occur when you contract the perineal muscles like when you are trying to stop the urine or feces. You have to do this contrations repeatedly.
One short solution is medications. Some patients are not willing to wait for these acts to produce results and instead demand medicines. I prescribe them 12.5 mg paroxetine at night and they are happy with the results.
Hope i am able to help with your concerns. If you have any further queries I would be more than happy to help you.
Dr. Srikanth Reddy
Psychiatrist and Sexologist