It happens to everyone!
Don't worry, I think everyone has a time where they end up eating a little more/differently than their diet suggests.
I went out to eat for the first time last week and I got sick! I think my body just isn't accustomed to the fat anymore!
So, I think there are many potential pitfalls and as long as you pull yourself out and get back on the wagon, you're doing great!
Keep on plugging! I'm cheering you on!