my opinion is that you should not worry about it you can start of with
multivitamin tablets and have good balanced food, exercise regularly
besides all this I suggest my patients the following…..
1.Practice and relaxation technique
2. try to distract yourself by thinking nonsexual thoughts (such as talking about some good films or games) to avoid getting excited too fast.
3. "stop and start" method:
during sexually stimulating activities when you feel like you are about to reach orgasm. Stop the stimulation for about 30 seconds and then start it again. Repeat this pattern until you want to ejaculate. The last time, continue stimulation until the you reache orgasm.
4. The "squeeze" method:
ask your partner to gently squeezes the end of the penis (where the
glans meets the shaft) for several seconds when you fell to ejaculate. Stop sexual stimulation for about 30 seconds, and then start it again. you can repeat this pattern until the you want to ejaculate.
You can apply a local
anesthetic cream to the penis to reduce stimulation. Decreased feeling in the penis may delay ejaculation. Condom use may also have this effect .
medicines are available in market, i will advice you first to follow and practice these methods
Hope I have answered your question. If you have any further questions I will be happy to help.
wish you a good health