Hi
Thank you for using justanswer.
It seems like you are having a condition called premature ejaculation.
OVERWEIGHT and LACK OF EXERCISE are obviously main factors in such cases alongwith other possible causes. So you must exercise regularly and lose weight.
Obesity(truncal specially) lowers down serum testosterone level and that also plays a part. So if need comes up, ask your physician to check your serum testosterone level.
Viagra, Cialis, Levitra does help for such cases but at the same time these are also associated in some patients with side effects like flushing, headache, or blurred vision etc. But overall, these are effective in most of the patients.
you can use diets high in serum Arginine level. Also herbs like Yohimbine, and Ginseng are helpful too in some patients.
Most important out of all , is that you must regain confidence in yourself. Anxiety of failure to perfrom is a major cause of premature ejaculation.
So you must exercise regularly, lose weight, keep your BMI below 25, and talk to your local physician for trial of prescription meds like viagra or cialis.
Keep it up for good health
MD
Diplomat American Board of Family Medicine