If it is still too young, strengthen physical exercise to enhance physical fitness and use drugs with caution. You can try to squeeze the penis every day, from under the penis to the glans penis, until the erection lasts until you can't stand it. Keep exercising for a while and see if there will be miracles. Edema will appear at first. Drink more water and urinate more, and you will recover on your own. Take it easy. Just try it. Good luck!