First of all remove all myths & misconceptions from your mind about masturbation.
In fact, Masturbation is completely normal & doesn't have any bad effect to the body and mind
All those concepts that masturbation leads to stunted growth
and hair loss is baseless.
Height of an individual is determined by Genetics, Environmental & Nutritional factors and Hormonal factors (most important the Growth Hormone
secreted by pituitary gland
Similarly...there are a number of reasons for hair loss.
So..please leave all these thoughts...it's better to meet a Dermatologist
and get a solution.
There are so many new therapies for management of hair loss.
Also...make sure that you are taking a healthy & balanced diet, exercise regularly & avoid stress.
One more thing...avoid consuming any over the counter medication
which claim to increase height...it may be harmful.
Wishing you Good Health.
Thanks and take care.