Brief Answer:
follow the advises.. maintain a healthy lifestyle..

Detailed Answer:
Hello XXXX, Welcome back,
Thanks for following up with the details,

Well, to begin with, you should note that at such young age group, the primary reasons for this is mainly psychogenic (mainly performance anxiety, stress and over indulgent thought process) rather than anything organic (any organ dysfunction or impaired body metabolism)..your too young, have faith in yourself and follow the advises below, you should be observing the changes..

First of all, the length 6cm (I believe you've measured it during the full erection, if not then do recheck it again) although may sound and look petit but it's not, don't focus on the length too much, then you'll loose interest in the actual act and resulting in failure of performing the act..

At such young age, I'd not encourage you to take any medications, as the primary cause is mostly correctable with timely intervention in an orderly fashion..

Follow the advises (read thoroughly, take your time, don't rush in to everything altogether at the same time, give it some time to act properly)-

- Eating healthy is one of the thumb rules of being a great lover. So the heart healthy foods fill your stomach, flushes out bad fats and also helps you be more energetic in bed

- Have diet mainly home-cooked, with good portions of lean meat proteins (eg. chicken, fish etc.), limit red meat (if you do), have eggs daily (1-2 eggs per day is fine).. avoid junk foods in any forms.. no excessive deep fried/ fast foods strictly.. include fresh green leafy vegetables in your daily diet.. have a bowl of salad every day (throw in some small chunks of anti-oxidant containing foods like black olives, red onions, red tomatoes, olives, spinach, dry roasted pumpkin seeds, almonds, sesame seeds, mushrooms, chickpeas, red beats, carrots and garnish with small amount olive oil and oregano and/ yogurt - have it daily, you can throw in some seasonal fruits chopping in to small sizes too)..

- Avoid processed and packaged foods, always try to eat fresh, organic foods, have fresh fruits instead of packaged fruit juices..

- No smoking strictly (if you do), alcohol in very moderate amount too (if at all consume)..

- Try to snack healthy instead of junk foods, have a handful of high zinc & antioxidant containing foods eg. cashew,almonds,raisins,pistachio, dry roasted/boiled chickpeas, yogurt daily..

- Always try to maintain a healthy 6-8hr sleep routine daily, it's extremely important.. exercise daily (30-45 min jogging in the park, free hand exercises etc.)..you can also practice 'Kegel's exercise', do watch a tutorial video in You-tube prior to this - I'm sharing you the link here -

https://www.youtube.com/watch?v=Tncp-ty9-q4

- Try to replace your daily wheat/flour to whole-grain.. try to focus on having fruits like banana, watermelon, berries, grape-fruits, dates, figs, apple, pomegranate, cherries, strawberries..

Moreover, don't focus on the erection/length/duration parts, and enjoy the moment when your with her..always try to involve in a bit of foreplay before hand..

Have confidence in yourself, you can do it..follow all these and you'll notice the changes within a matter of time only (please note that overnight miracle is beyond the scope of any medicines, so follow this gradual and assured way)..

If despite following this for few weeks, you feel there's not much improvement, then I'd suggest a face to face clinical session by any Urologist / Sexologist for a detailed evaluation in to this..


Take Care
Kind Regards

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