Congrats on the accomplishment. But, I am afraid that I must officially welcome you to the world of post-weight loss. It feels great... but there are some catches. This is just one.
I also lost a lot of weight (265 lbs---->160 lbs) and found that while my bodyfat percentage was fairly low and my abs starting coming in, i had the annoying flabby skin around my lower ab region.
Here's what it is.... when you were overweight, your skin was stretched out to make way for the fat in your stomach. Upon exercising when you lost weight, the fat disappeared and the skin shrunk down. (I would guess that there are visable stretch marks that are kinda bunched up around your stomach?)
The best thing you can do for this is wait. It's been over a year since I finished losing the weight and the skin is starting to get back to it's normal state... but it's hard. If you want something to put on it... i would suggest a strong Vitamin E cream or oil. Apparently the Vitamin E helps with cellulose and stretch marks, but it ain't gonna cure it overnight. S.A.N. nutrition makes a product called "Lipoburn" that is for spot reducing fat thermogenically and i've heard that CAN help. I've just ordered it and will let you know how it goes.
Don't get defeated, your accomplishment is great. In time, that stuff will subside and you will reap the full benefits of the hard work you put in to get into great physical shape.
wc