Brief Answer:
need details..

Detailed Answer:
Hello Mr.XXXXXXX, this is Dr. Chintan Solanki here.

Your problem is common problem of current time. As you mentioned one inch of penile length of yours, it must be in normal (flaccid) position. I want to know,"length of your penis in erect position"
As penile length is not matter for sex ,if it is at least 3 inches in erectile position.

If you are not suffering from hypertension, I would like to start with sildenafil or tadalafil(which can be used in hypertensive patients also). These medicines can be taken before sex on required basis only. They cause side effect of headache commonly.

Other option is a newer molecule methylfolate plus phosphodiesterase inhibitor combination (tetrafol plus - trade name) which might help in some patients for increasing vascularity during erection.
Both above treatment options must be tried preferably under doctor's supervision to prevent major side effects.

I suggest please go to psychiatrist/qualified sexologist, narrate your problem in detail. You will be examined physically and then medical treatment will be started.
I would like to know also about, "your past sexual history in terms of performance,marital history and any medical/surgical history if any."

Hope I have answered your query, late me know if any further information needed.
Thanks & Regards.

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