Brief Answer:
Your problem is likely psychological, you can come out from it

Detailed Answer:
Hello,

Thanks for writing to us.

Japani oil is not all any approved treatment for sex problem.

It may contain some local anesthetic that is why you felt no sensation while making relation on that day.

You are feeling hardness in penis in morning that suggests you do not have any specific physical problem.

For good erection constant exciting erotic feelings must be present in mind. If your mind is diverted to something else apart from sex, erection is going to lose. Many times due to fatigue, stress, physical problem or excessive workload man cannot perform well in sex. This is not permanent failure but only occasional problem. You failed once due to side effect of japani oil. When person becomes apprehensive about such occasional failure and constantly thinks about his ability to do successful sex while he goes for sex his mind diverted from exciting/erotic feelings and penis loses erection. This anxiety might be responsible for failure of intercourse as well as masturbation. This is called performance anxiety.
This is purely psychological problem, no physical/pathological problem at all.

First of all never use such type of oil and specifically any product for sex problem without doctor's guidance.
To come out of this man must not think actively about maintaining erection or arousal while doing sex.
To get rid of performance anxiety help of partner/wife is also an important aspect.
Whenever you go for sex, spare enough time in foreplay. You should not think actively about erection, your mind must be occupied with sexual/romantic feelings. During foreplay your wife should try to arouse you and note that your penis gets erection or not. When she feels that penis is sufficiently erect she herself should try to put erect penis in vagina gradually and you should continue your foreplay feelings without being conscious about erection. You must try to enjoy and only enjoy. Once penis is able to enter in vagina and strokes starts it is easy to complete successful sex.

If your partner is not aware about this situation you can do on your own. Relax yourself. You just should try to do sex without being conscious about erection. Enjoy without thinking of your ability to maintain erection.

Even after 34 weeks with above measures you cannot do sex well, other option is low dose clonazepam or lorazepam before 2 hours of sex. This anti-anxiety medicine will reduce your apprehension and make you relax to have successful intercourse.

And last but not the least if you face problem after above measures another option is 5-PDE inhibitor group of drug like sildenafil or tadalafil. You can take it before 2 hours of sex for good erection. After 3-4 successful attempts you will have confidence and you can do without help of medicines later on.

Hope this answers your concern.

Regards,
Dr.Chintan Solanki.

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