So what you've done by eating so little food is slow your metabolism down to the point that you can't lose weight. At this point, when you start eating real food again, you're going to gain weight. There's no way you can't .. your metabolism is being damaged and you're probably losing lean muscle at a huge rate, and your whole body needs time to recover.
At your weight, you should be eating around 2500 calories (of healthy food) to lose weight at a safe rate.
First thing you need to do is start eating. Real food, not junk.
From there, you can GRADUALLY begin lowering calories again until you're losing an average of 2-3 lbs a week. At your weight, that's a safe and sustainable rate of loss.