Hiya, I was exactly the same, started on a Saturday, but didn't make it through a whole day till the Tuesday!!! Once I finally done the whole day on Tuesday I knew I couldn't give up.
Just keep reminding yourself why you want this??
I once I've dished my daughters dinner up I make myself busy so I'm not hanging around looking at the leftovers. I'm now on week two after a 8lb loss and I'm feeling great it really is worth it. Stick with it and by Monday/Tuesday your be feeling good too. Xx