thank you for your query in healthcaremagic.com.... first of all, masturbation for 4-5 times a week does not cause any harm to the penis or alter the seminal fluid by any means...so dont worry for that.... whereas there is no sure procedure or medicine to increase penile size till date...though some natural methods or pills are available in the market but they cant give sure shot results...only problems like erectile dysfunction or decreased libido etc can be treated with medicine...well anxiety etc can also be a problem with normal sexual habits so dont be worried.... so i would ask you to visit a PHYSICIAN and from there you can be referred to any other specialty if required..... hope this was helpful... regards