900 calories is really really low, I'd be knawing my arm off with so little food. Plus you may be setting yourself up for cravings and be so hungry that you will eat everything in sight after a few weeks of eating so little calories. You are also slowing down your metabolism and when you plateau, and you will

, you won't be able to reduce your calorie intake because you'll already be so low. My suggestion would be to up your calories gradually to at least 1200 to 1400 cals/day minimum and see where that takes you. Everyone is different when it comes to their calorie range so you have to experiment...
You can also post your fitday account under your avatar if you go to your User CP and put in your account name... and we can scrutinize and analize it

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Hope this helps and keep us posted on your progress....