Brief Answer:
Might be physical or psychological; follow as advised

Detailed Answer:
Hi,
Thank you for posting your query in healthcaremagic.com
This is Dr. Swarnava dattagupta answering your query.

I understand your concern.
In short, erectile dysfunction has got two broad causes- one is physical and the other is psychological. There can be combined presence of both also. In any case, physical causes like heart disorders, diabetes, hypertension, peyronie's disease etc are to be ruled out. You have not been to a doctor but however got tests done, so most of the causes are ruled out as the reports are normal. Now, alcoholism and smoking are two other common causes. You have stopped alcohol intake, reduced weight, now its time to stop smoking. It will be really helpful.
Now the next cause is psychological. It is very common and can be treated effectively. Depression, stress and anxiety is quite common these days and it increases incidence of erectile dysfunction.
My general advice to all such patients is-
Weight reduction, stop smoking or alcohol intake.
Reduce stress and anxiety.
Drugs like sildenafil, tadalafil are quite effective. Similarly, newer drugs like alprostadil are also good.
Psychologist visit or counselling are important in persistent cases.
Penile pumps and surgical interventions in resistant cases.

Dont worry as of now. I believe the basic lifestyle changes and drug management will be sufficient.
You can consult your treating or family doctor about the above.

Hope i have answered your question.
If you have any further questions i will be happy to help.
Regards.

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