Effects of Masturbation on Penis

Sometimes I only masturbate about once a week and sometimes it is up to once or twice a day. I am not sexually active but have some concerns about my penis. The skin right below the head of my penis when limp has gotten kind of loose. It is stretched out a little bit. There is also a dark ring at the bottom of this stretched area. Also, on the bottom of my head there are two little reddish white bumps. The bottom of my head also gets a little reddish at times. My penis also curves to the left.
Thank you for your help!

From you description, your penis sounds perfectly normal, but you may want to consult your doctor just to be sure. It is not dangerous to masturbate.