Hello
Masturbation is perfectly normal and only those people worry about it who develop unnecessary guilt along with it.There is no need to worry about it.
Penis has normal slight curve and is perfectly normal.
There is no way to increase the size the size of penis and there is no need to increase it.
Whatever size of penis you have is sufficient to derive and give adequate sexual pleasure.
It is better to come out of this flawed myths and notions about penis and masturbation.
Don't do the masturbation just for the heck of it.
Do it whenever you are sexually aroused naturally.
Although doing masturbation daily is not harmful medically but still you must indulge in regular exercises and yoga and concentrate in your career rather than thinking of penis and masturbation.
Thanks and best of luck.

Masturbation is a physiological phenomenon in young unmarried males. It has no deleterious effects on the body. Backache may be due to other causes. masturbation in excess may cause run down feeling , weakness and lethargy. The only way to straighten your penis if it is truely bent is surgical intervention. The dimensions of the penis depend upon the optimum usage of the organ. Only proper heterosexual intercourse can exert a positive effect on the organ.

Hello,
Welcome to HCM,
Masturbation is a common and normal practice among unmarried. As it does not cause any weakness, you should not worry about it. Back pain can be due to other causes, for which you should consult an Orthopedician. If you always use a particular hand for masturbation & grip it from side, your penis can become slightly curved, which can become straight after marriage, when you leave the habit of masturbation. Particularly there is no exercise to strengthen it, but regular exercise of whole body and abstinence can improve the picture. Size increase till body grows only.
Hope I have answered your Query.
Wish you good health,