Early Impotence

I’m only 19,
The last year my penis used to get really strong erections. But after 3 weeks of 50jelq + 25kegel (after 5min warmup in hot water bath) it lost its strength.

I think that the problem is that I masturbate a lot. 1-3times a day, everyday.

Am I losing sexual desire? Losing hormones effect?. How many time should I hold without masturbating ?

I’m really sad, because it seems I half erection and takes much more time to reach maximum length.