What does the calorie coach do?

Can somebody please tell me what the calorie coach does and what it means.  I have a down thumb sign but am in my calorie limit...

Don't pay too much attention to it.  It could mean you lost a lot of weight since the last time you logged and it thinks you are losing too fast.  Or it could be that you gained a pound or two and made it unhappy. 

Thanks!  LOL.  I kept scratching my head but couldn't figure it out!

i agree! i am so confused why it's mad at me for losing 4 lbs. is that because of the whole weight rebound effect?