Brief Answer:
Looks like erectile dysfunction.

Detailed Answer:
Hello,

Unable to maintain erection or partial erection with early ejauculation can be either due to psychological reasons or some underlying cause.A doctor's counseling is suggested in most case to find likely cause of it.

At your age psychological issues or mis match with partner are more likely causes.Psychotherapy can prove rewarding.

Meanwhile drugs assisting erection can be helpful for getting and maintain erection.

Making life style improvements (for example; quitting smoking, and exercising more) can be helpful. If you are on some medications then work with doctors to select medications that do not impair erectile function.

Some alternative treatments available are as follows but to considered only with consultation of doctor.

Inserting medications into the urethra, Injecting medications into the corpora cavernosae, vacuum constrictive devices , penile prostheses etc.

So dont feel embarrassed to see doctor.Doctors are well aware of the issues and they wont make feel embarrassed.

I hope I have been helpful to you, Please ask if there are any doubts.Regards

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Brief Answer:
In that case you can hold exercises.

Detailed Answer:
In that case you can hold exercises or do whatever is possible for you.Other way is you can do stretching, breathening and yoga exercises.

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