Weight Loss followed by gain

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I am a bit perplexed and demotivated.
I have started the insanity program as well as doing Zumba 2-3times a week and the treadmillfor 10mins prior to the Zumba class.

My calorific intake has been restricted to 1200 and i rarely if ever go over this unless it is a Friday or Saturday when I am dirnking. If I do drink then I ensure I do not eat more than 900calories of food that day.

I first Weighed myself in the morning last week Weds (18th) and was at 144.5lbs. Over the course of the following days my weight steadily dropped and on Sunday morning when I weighed myself I was down to 140.0 which I was very pleased with of course.

However yesterday morning I was back up to 143.2lbs and this morning I am at 143.6lbs - How can I have put on over 3lbs in a couple of days when I have not over-eaten and I work out daily? Fair enough I do not kill it in my workouts but the diet alone being below 1200 should mean I am at least plateauing or maintaining. I just do not understand How since Sunday I gained 3.6lbs.

I am thinking now that I just want to go back to pigging out - I have been on this diet for two weeks and was ecstatic with a 4lb lost. To know that in reality it has only been 1lb given the amount of work I am putting in is devestating.

My aim was 2lbs a week loss but then I realised that the only people who achieve this are generally obese to begin with so I settled on 1lb a week. I am now losing 0.5lbs a week if that it seems!

I am 27year old female, 5ft3.7 Was 144.5lbs and I am now 143.6lbs

A year ago I was a size 8, 125lbs and had never had to work out or diet to maintain my figure.I just want to go back to that.

I moved in with my Boyf and piled on the pounds and I am so depressed with it all to be honest. I am working my fat butt off to get back in shape and all for a 1lb loss in a fortnight!!!

Any tips on how I can lose at least a 1lb/week?