Still pretty young for a PH, especially this one is methylated I believe, sure up your diet and cardio routine, if you are carrying a lot of bodyfat you will loose a good bit before any muscle loss, me personally would never dable with this type of prohormone, i suggest you wait until you are at least 21, and if you insist on taking something take something non-methylated...actually better yet do a lot of research and don't take any PH's
What is your estimated bodyfat %