Hi,
Thanks for posting in HCM.
I have read your description and understand your concern.
What problem you are describing appears to be more of psychological than physical one.
Sometimes, it happens for few men to have difficulty in erection and sustain it for long. But this can be overcome without any much issues.
Masturbation is a healthy physiological phenomenon and does not cause any harm to the body or sex life or
fertility. However, it should be spaced well and should not be overdone.
You can build you confidence by practising behavioural therapy like 'pause and squeeze' technique.
Include in your diet - almonds, banana, pineapple, saffron, cardamom, figs, honey and pumpkin, which are known to increase the blood flow to the penis and help to initiate and sustain erection.
You can take Tablet.
Tadalafil about 30 minutes before the act to have good erection, when you feel necessary.
Also, doing
meditation would help you to overcome
anxiety and keep your mind calm and healthy.
Over a period of time, your confidence should improve and you should be able to sustain better.
Hope the information provided would be helpful.
All the best.