That is not really a diet you were doing - that is dangerous stuff to play around with only eating lean protein. You will lose muscle mass and your metabolism will lower. You can lose hair and damage your thyroid.
Do you want to know how fast you can lose on Atkins? We do not know as we are all different. The way we chose to look at it is that it is not a race. We are changing to becoming healthy, eating whole food and plenty of vegetables and we are in it for life. Are you ready for that kind of a change?