So frustrated by dining hall nutrition facts!

Either I use the dining hall's nutrition facts on their website (often readjusting to fit what I think I actually ate) or I have to look up individual pieces and estimate. However I do it, I always feel like what I end up with is wildly inaccurate.

Today, I ate a gyro. This was not the giant overflowing meat extravaganza you get in restaurants. It was a 6" pita with 2 approx. 2" x 6" x 1/4" strips of meat, with 2 tbsp tziki sauce and about half a cup of diced tomatoes. I look at their website and it says 1002.92 calories per serving. It doesn't say how much a serving is, or what it weighs or anything. This seems utterly ridiculous for the amount of food I ate. And I can't find any calorie info for plain gyro meat anyway!

Do you think this is accurate? I have to eat there a lot, and I think getting the calories so wrong every day is going to make a big difference over time. It might already be doing so. I'll just be really bummed if this is right because then I'm up to 1600 today already.