Hi, there!
Maybe you could post a few days worth of what you're eating? (Put absolutely everything!!!!) You might be doing something that's tripping you up that you'd never suspect.
Are you drinking plenty of water? If I don't drink at least 4 litres a day, I stop losing.
And yeah, unfortunately, it might be the Atkins bars tripping you up. I've never eaten them, but I love the Pure Delight chocolate bars and I sadly have come to accept the fact that if I have one, I will NOT lose any weight for a day or two.
Some people are stalled by coffee (which has carbs in it, btw.) Also, some people aren't aware of the 'hidden' carbs in other things, like cream.
Don't give up yet!!!! You might just need a few dietary tweaks to get you losing again!!!!
Good luck!!!