I suspect what's happening is something that we, on the board here, refer to as "skinny
fat". It mean that you've mostly lost the weight you want to lose, but you have no developed muscle and you're out of shape. That means you may be a healthy weight, but you're flabby.
Cardio is great for burning
calories while you're doing it, but what you really want to do is build back the lean muscle you've lost (or at least maintain and strengthen what you've got). Weight lifting and
body resistance
exercises are the best way to do that.
Yes, you can do those at home with a set of dumbbells. I would suggest that you read the thread in the exercise area called "The Conceptual Side of Weight Lifting" by Steve. It's sticky posted to the top of the forum.
If you follow along with what he says and work your muscles to build strength, I think you'll see a tremendous difference in your
body in a very short length of time.