losing weight too fast?

So I've been doing really well with counting calories, eating healthy and excercising.

My only concern is that I've already lost almost 11 pounds this month (and there's still about another week to go). This is a bit more than the recommended weight loss per week (2 pounds).

I eat between 1200-1400 calories daily, have really small meals constantly throughout the day, do resistance training 3 times a week for half an hour and do 30-60 minutes of cardio on the days I'm not weight training (but I do the calculations to ensure my deficit is no more than 1000 per day).

Should I be worried? I just want to ensure I'm losing weight the healthy way and that I'll be able to keep it off. Thanks for any input in advance :)

Is this your first month of healthy eating and exercise?  Keep in mind it's common to loose 5 lbs the first week of dieting.  How much did you loose your first week?  Could this perhaps be the reason for the 11 lbs and still a week to go?  If you continue to loose rapidly I would contact your dr about loosing to fast, but if this is your first month, I would attribute that 11 lbs this month in part to that.  If this isn't your first month, that whole tidbit of information probably doesn't apply.

It may be nothing to be concerned about, but whenever there is a rapid change in weight and it's not the first month of a new diet/exercise program, it doesn't hurt to be sure all is medically OK.