You are doing great! And if you feel tired/sleepy, then rest. Your body is detoxing the toxins out of the system, which is the same process your body goes through when it tries to rid itself of disease. Give your body the time and space (and by space I mean rest) to do what it was designed to do.

It's amazing how efficient our bodies are when we allow it to do its thing and don't intervene with pills and other silly interventions, isn't it?

Keep juicing lots of fruits and veggies! Don't deprive yourself. The point is to shut down your digestive system, not to deprive yourself of basic nutrients.

Day three is a huge milestone! Keep it up. The next major milestone is day 5, because that is when your system finally shuts down. After that, it's 7 days, because you have reached a full week. Keep it up! Day 40 (or however many days you had planned to do this) will come with or without your success and more healthy self. It's up to you how you will arrive.