Oh no, why did you give into the naughty crisps! Well at least you admit what you have done now. I admit if I had a bag of Doritio's it would be demolished within a few minutes Wouldn't you be in ketosis after 5 days, never mind. Pick yourself up and restart.
It is great that you are re-starting and I myself have had a huge binge during christmas and i'm ready to get rid of my gain. I have finally come to terms with how huge I am and want to do something about it.
I am going to low carb it and eat more salads and vegetables ready for my start on Monday.