Dear Welcome to HCM We understand your concerns I went through your details. Please understand masturbation is not unhealthy, rather it is natural and normal activity. A person at your age can safely masturbate twice or thrice a week. No anxiety regarding that. Watery semen could be due to more frequent sexual ejaculation. The thickness of the semen changes according to many things including the above. Thickness of semen is never a determining factor regarding your sperm health. May be, your such anxieties are the reason for your erectile dysfunction. You also said you are feeling there is no hardness in your erection. I suggest you to ignore these areas and enjoy sex without apprehensions. If you may desire, you can consult a psychologist for sexual counseling. If you require more of my help in this aspect, please use this URL. http://goo.gl/aYW2pR. Make sure that you include every minute detail possible. Hope this answers your query. Further clarifications are welcome. Good luck. Take care.