the last two weeks, i have been eating between 1200 and 1500 cals. i have exercised for over an hour a day. i haven't lost anything!!! it's weird because when i did this before, i losr alot of weight quickly! i lost 20 lbs in 3 months recently by doing this-now i have the last 20 that i am determined to get rid of. what could be going on? what do i need to do differently? please help!