You've had some great advice here Veronica...
Just one other thing I wanted to add... in the past, EVERY single time I have started up a new exercise or dieting regime, I always come down with a cold or flu with 2 weeks. I don't know what it is, or why... but they do say that when doing strenuous exercise your immune system is weakened - as opposed to moderate level exercise which boosts your immune system.
Just thought I would add this thought in as well....