Portion sizes?

What do you all call a portion size? If I am having a salad I can sometimes have half a bag or a whole bag with 2-3 tomatoes....is this wrong? Also how much chicken would you eat if you cooked a whole chicken?
I think I maybe over eating but over eating on the things we are allowed IYKSWIM?

a portion of meat is supposed to be the size of the palm of your hand or one chicken breast i think but it depends which diet you are following, eg SW you can eat unlimited amounts of lean meat etc and still lose weight. i reckon as long as you eat till youre satisfied and not just for the sake of it and also stick with the 5%/100g and <15g fat per meal you cant go wrong.. and as for counting salad portions, are you mental girl?? xx