Thanks for query.
You are under weight,but forget that it is due to masturbation
This habit never cause any problem.
try to increase your weight.
Take more nourishing diet,high protein like pulses,cereals,milk,eggs,etc.
take dry fruits,
more green vegetables,fresh fruits.
To have sex urge at this age is very good but learn to control.
Coming out of depression
leaving false ideas of your habit.
Never think of suicide
,bright future is waiting for you.
ok and take care.