Brief Answer:
No intervention is required.

Detailed Answer:
Greetings.
To start with I would say that it's not a problem.
a five inch is a perfect average size.
and moreover it's just the first two inches of vagina which is sensitive.
secondly still if you want to try, You can try stretching exercises only after consultation with your doctor as he should examine it first and then only he need to teach you the manoeuvres only if he thinks it's indicated.
Regarding the pills. It's a very mixed review topic.there are various pills available in the market. your doctor would be knowing about them. but with out getting yourself examined thoroughly there's no point for any intervention.
what you should know is that you have a perfectly normal size.
hope this helps.

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