Oh no, I'm really feeling for you. I used to have days like this, yo-yoing between good days and bad, which is why it took me so long to lose anything between January and May.
Why don't you start keeping track of everything in your food diary again? I find it really helps me, especially when I'm forced to write down the naughty stuff.
Just remember though - yesterday was only 1 day. You can pull it back if you go straight back onto plan. Have a think about your goals - should give you the motivation to carry on.
Big hugs for you hun xxx