masturbation is actually a normal behavior. but it should not be excessive in frequency which may cause fatigue and back pain. you need not see a doctor right now. just divert your thoughts into much important things in life like studying enjoying outdoor sports finding good friends etc. try to reduce the frequency of the practice to about twice or thrice a week. this is the transient period in everyone's life when urge to explore and also trying to experience new things especially sexual pleasure occurs. as you are physically and mentally mature the problems that you are facing now will resolve spontaneously. apart from this as you said "proper diet and lifestyle changes" are to be followed: eat nutritious foods (encourage fruits vegetable salads nuts cereal sprouts). limit processed and deep fried foods. indulge in outdoor sports which you are interested like swimming etc. sleep adequately at least 7-8 hours as it is much needed for your normal growth too. avoid smoking and drinking alcoholic beverages. just follow these for a month and let me know how do you feel. get back to a sexologist online for further follow up --> <link>
to overcome my depression anxiety and stress i started masturbating. i feel weak.