I masturbate every 3 hours ? is it bad?

Time-consuming: I would not place a value judgment of "bad" or "good" on it, but it sounds like this activity is absorbing a lot of your time. Is it disrupting work, relationships, other activities? Doing anything every three hours sounds compulsive. Please consult a psychiatrist skilled in compulsive sexuality disorders. Not to say this is what you have, but for doctor's skill. See http://psychcentral.Com/l.