How many calories do I need?

huckleberry0070

Okay, so I'm 5'4" and weigh about 120. I'd like to lose between 5 and 10 pounds, but mostly just firm up my middle and tone my legs. I've been doing P90X for a couple weeks and also get an hour of cardio (running and/or walking) every morning. I have really been struggling to figure out the right caloric intake to help me lose weight and power through my workouts. I calculated that my BMR is 1365 and my TDEE is 2342. I figured this based on an activity level of 5/6 hours per week strenuous exercise. If I include a 15% calorie reduction, that puts me at 1991 calories per day. If I do the activity level 7 to 21 hours per week strenuous exercise with a 15% deficit it puts me at 2193.

The thing is, I'm trying to follow the P90X nutrition guide and it recommends 1800 calories a day (estimating that you burn 600 cal with the workouts). I got a heart rate monitor and have been tracking the calories I burn and it usually ends up being between 800 and 1000 per day. I don't quite understand the BMR thing but if I'm only eating 1800 and burning 1000, I would be dropping below that, right? That being the case, does anyone have any idea how many calories a day I should shoot for to burn fat? I'm nervous about going too high but in all the message boards for P90X when people hit weight loss plateaus they are told to eat more... should I really be eating as much as 2000 calories or even 2200?