Frustrations

On May 29 I got below 170 with a weight of 168.8.  Since then I have bounced around between 167.5 and 170 - though only in the 170s once during that time.  I have no idea what is going on.  Since I have kept perfectly to my plan and I have had some days that I have burned over 4,000 calories, this should not be happening.  I should be in the low 160s by now.  I don't know what to do.  I know what I want to do - I want to go cry into a milkshake and a pizza.  I'm not going to do that, but I want to.  I know that my plan works, if it didn't I would still be 245, but this is driving me insane!