11 pounds in 8 weeks

[hooty mcboobs]

I started lifting seriously around 8 weeks ago, and I started at a weight of 194 after a month of drinking, eating Burger King and basically doing nothing but going clubbin' (I was on vacation). So far I've lost 11 pounds (to a weight of 183), while taking Xenadrine. I'm not sure how much my bodyfat was then or is now, but visually, I have smaller lovehandles and belly.

I modified my diet from 3-4 meals a day of fatty fast food to one where I eat 6-7 small meals that are packed with protein and only a moderate amount of carbs; about a 30/40/30 carb/prot/fat ratio. I take a multi-vitamin in the morning, vitamin C and E, 1200 mg of Lecithin, and Evening Primrose Oil daily. I have 1-2 protein shakes (either Designer or Optimum) a day to make up for some protein that I may miss in my solid food.

Also, I started lifting 4-5 days a week while doing 3-4 days of cardio in that time. My split is shoulders/traps; chest/back; legs; bis/tris. In this time I've grown about an inch vertically (from 5'10.5" to 5'11.5") , while my muscles have gotten much more defined and larger.

My question is this: is this rate of weight loss slow enough so that I haven't lost any muscle, maybe even gaining some, while cutting bodyfat? What can I do/ take to lose an additional estimated 5-8% body fat in the quickest amount of time? I estimate my body fat % to be anywhere from 13-16% as of right now.