*Scratches head* 
I'm very confuzzled. This morning I was at level 3 with 79%. Apart from checking the forums a couple of times today i've done nothing apart from look after my daughter (who's home from school ill) and fall asleep with her on the sofa 
I'm now at level 4 with 31%!!!! How does this work? If anyone knows and can stop my brain from overheating trying to work it out i'd be very grateful 