Calories and the rest

I had surgery 8/1, and at this point my nut told me to take in around 800 calories.  I tracked today for the first time, and already I'm at 1085 without eating dinner yet.  I'm 6'-3" and have lost quite a bit, but I've been bouncing around weight wise for the past couple weeks. 

Here's what I ate:
Shake w/ Peanut Butter - 33g protein, 350 cal (PB drove it up, the shake is only 160)
Cabbage - 5g protein, 216 calories
3oz Turkey Salad made with Low fat mayo - 25g protein, 204 calories
4 slices of cheese - 18.6g protein, 315 calories (this killed me when I realized how many calories)

So, I'm 285 over and haven't made it to dinner yet.  I plan to cut out the cheese, because now I realize that is not necessary - I need to find lower calorie snacks. 

Is 800 unreasonable for my size, or am I just eating to much?  I don't feel like I'm stuffing myself, I measure everything out and stop if I'm satisfied, but I worry that I may be causing my stall.

Ditch the PB in the shake.  This can be a real bad habit and drives the shakes up to a calorie point that can be dangerous unless you are a workout demon.

and probably ease up on the cheese.  depending on how far out you are 800 might be right or to low. 

I have found that my most effective sessions with my NUT are when I have information and we discuss things.

Last year my nut session ended with you need 1440 cal a day and 65g of protein.  This last appt 3 months ago I went in with samples of my food journal my workout logs Metabollic testing results and fitness goals I was working towards.  She moved me to 2100-2300 cals and 150-180 grams of protein and 30g of simple carbs.

These people work for you so it needs to be a dialogue.  I do the samething with my surgeon and his staff.  I give them the full picture before we talk food.  Kind of hard to tell someone to eat 1200 calories when they burn that at the gym or running 5 days a week.