Actually, the description in these threads seem to suggest otherwise: "You need to start at day 0 and you need to post preferably everyday in this thread until you reach 21 days. When you reach 3 weeks, you leave this thread for ever" So you should not go back and do three weeks before taking on the 21-dayer again. Once you reached the new goal you can move until you've beaten that goal, etc ^^, Hope you feel better soon!