Smelly Starter

My starter is nearly 2 weeks old and I have been religiously tossing out half and replacing it with like amounts of flour and bottled spring water, every day. For the past week it has been smelling slightly like alcohol ... til today .. and today it smells like acetone. It is very much alive .. bubbling like mad, and when I feed it, it raises to nearly double wihin a very few hours. Am I maybe tossing too much and should be only discarding a couple spoonfulls ? It's in my bedroom where the temp is pretty close to 74 all the time. Whatever suggestions you may have I welcome.