This is perfectly normal. Our weight is not a static number, rather it's a vital sign, just like your body temperature or blood pressure. Depending on the foods you eat, the things you drink, sleep, hormonal shifts, even the temperature outside, your weight will fluctuate as much as 10 lb in a single 24 hour period!
This doesn't mean you're gaining fat, or doing something wrong. This is one reason it's recommended to weigh about once a week, on the same day, under the same circumstances, wearing the same clothes (or none at all.) Most people find they weigh the least first thing in the morning, before breakfast, after going to the bathroom.
Don't stress. You had fluctuations when you were on Atkins, you just likely didn't notice them. ;) We all have them!
Writer, mother, wife, and breadwinner. I love to run, but running doesn't love me, so I'm switching to my low-impact bike.
I'm not pregnant, just fat: My blog. fatnotpregnant.blogspot.com/
| current weight: 186.4