Calories is a simple matter of measuring the exact energy of a food.
Weight loss -- and how calories affect our extra fat -- THAT is a totally different story. This is all pretty complicated, and it affected by our metabolism, activity level, what we have been eating before this, etc. If you are GENUINELY hungry (ie hunger pang, tummy feels empty) and eat then, even if it is a lot of calories, no matter what it's unlikely for you to GAIN fat.
And calories your body recognizes -- i.e. "real" food -- are on the other end of the spectrum, on the happy, not gaining extra weight, not feeling sluggish afterwards, side.
So, for now at least, just eat good raw food, and you will likely lose some weight if there is some to lose. If you seem to be craving fat, go for the avocados or coconut or whatever. Just eat good raw food, and you're set for now.
And I don't know if you know about green smoothies yet. If you don't, here is a very quick summary: smoothie with some fruit and some green leaves, maybe some water and ice too if you like. It can be lots of fruit and a few leaves or whatever. This will probably help you with the headaches. You lose minerals when you're detoxing. This will help with that and also help you to detox through your bowels rather than with other symptoms.