As Mustang said, continue to eat, keep your protein levels up, and keep your immune system in shape. The last thing you need is to become sick during a cycle. If, however, you notice some serious complications, post again in the future with history, stats, training, diet, etc. Not that there is, but there's always a possibility there's a hole in your program. However, at 3 weeks, saying there is an error would be premature. Good luck and keep up the great work!
R33t