Net Calories

I am sure this must be discussed some where, and if there is a link I'd love to follow it, but I have a question about Net calories.

In general I do not eat my exercise calories. I eat healthy nutritional food and stick to my daily allotment of calories. This leave my net between 700-900 calories in general. Is this too few? Should I be eating my exercise calories?

I am losing weight. Slowly. Which I know is good, I just wonder if I shouldn't be loosing a bit more.

Any help would be greatly appreciated.
April