OK so lately i have been doing REALLY good with diet and exercise.
Ive been going and working out everyday in the morning, and then doing anywhere between 1-3 miles of running almost every night. Ive been keeping my calories in the 13-1400 range. I also eat about 4-5 small meals a day.

Well

this week ive been so busy getting everything ready for my daughters birthday party. Ive missed the gym 2 days this week, and I am not running because Ive been so busy! I have been staying within my calories, but when ive been eating its been more like 2-3 meals...I know everything will be back to normal next week, but ive put on a whole 3 lbs somehow??

So im a little confused...I figured staying in the calories would at LEAST keep me maintaining...

And whats even more interesting, is i checked my body fat and its down 1% since monday. How am i gaining if Im staying 13-1400 cals?

I can go up or down 3 lbs in a day due to water retention (that time of the month), too much salt or drinking alcohol. I would say don't weigh everyday...maybe once a week or even once a month. For me, and I know others disagree...weighing everyday messes with my mind. As a women, our weight fluctuates too much at different times of the month. Like others have said, as long as you are doing what you should be, just pay attention to a general downward trend over a month or two, not day to day.

water retention masks fat lost. I am one to weigh every day because I find that being aware of the simple ups and down my body goes through makes me appreciate the losses and not get overwhelmed with gains because I know it's cyclical. What has probably happened is your body is retaining water and trying to readjust in this "down time." It goes through a similar adjustment when you begin to exercise more than usual. My body is a big "adjuster," it wants to sit at a weight for awhile, bounce around in that area, feel the space out, get cozy, and then its ready to lose again.
i recently started doing yoga every single day and I was still plateaued, still plateaued and then in the past couple of days I've shed four lbs of water.
It's up to you whether you think seeing weight fluctuations is overwhelming, or if it helps you to kind of get in tune with the science of your body. For me, better understanding brings greater peace.

Yup. Water. Food. Waste. Inflamation. etc.

The scale can only tell you how much your body weighs. It can't tell you how much of that is fat and how much of that is other stuff. Unless you ate thousands of excess calories, you didn't gain 3 lbs of fat. Wait it out, it'll come back off.

Also- I nearly always see a temporary gain of a few pounds before I get a big woosh. I read somewhere that your body will fill fat cells with water before shedding them.

I think it's water, don't stress it.

Iused to weigh myself everyday but I stopped that. It was making me a mad woman!!! Don't do it!