What will you do to know that your nose and ears are in pure health?
The question is why do you doubt that your penis and testicles are in pure health?
It is possible you have doubts due to paucity of accurate educational facts about sex and sexual organs. It is possible that before marriage you want to be sure you are capable of sex and begeting children.
If that is the case and you want to know what is normal what isn't, whether masturbation has caused any harm or no then I recommend seeing mydoctortells dot com. You will benefit by finding all details about sex on the website that your parents and teachers didn't tell you.