I'm a big fan of fitday.com - I count calories too, not to lose weight but just to make sure I'm getting a healthy amount to maintain my weight. Also I can check to make sure I'm not getting too much fat, that I am getting enough fiber, and that I'm getting all the required nutrients. It's a pretty cool site and really easy to use! 750 is definitely way too low. You probably need at VERY LEAST 1350 cals a day.