HEY!!! I just recently turned 18 too!! Congrats. I am a female, about 175-180 lbs (I am at college and I don't have a weight machine) 5'6". I am sorry that I don't have an answer to your question :( but I just started this journey to change my life as well. I finished my day 2 of the water fast!! I am so pleased. The reason I am writing is that if you want to be buddies through this?? I haven't told anyone about this because I am afraid they will kill my motivation!! So it will be amazing to have someone to talk to about this!
If you want to be buddies :) my email is: monatanu@gmail.com