I'm really concerned about my penis size. I'm 19, and my current size is about 5 inches, but I would like it to be around 8 or 9 inches, both in length and width. I'm quite active and physically fit, but I find that after masturbating, which I do a couple of times a day, I feel really tired. I also do at least an hour of exercise every morning. Are there any exercises or diets that can help me increase my penis size and improve my sperm-holding capacity? Would love some guidance on this.