6 weeks to change

I had been talking to my mom this morning, who works out, eats well for the most part and has had a personal trainer before. She told me that it takes about 6 weeks for your body to get used to whatever your doing and say "it's ok to lose weight and up the metabolism now". Holy crap. I'm almost 2 weeks in and I feel a little miffed about this news. It seems so far away!!