I have my inventory set to num 0,skills to num 1 and journal to num 2.
The issue is I have my healing potions set to key stroke 0 in the action bar. Everytime I press my num 0 key to open my inventory it also uses up my Health potion. Every time I press to open my skill tree using num 2 it sets off my skill sitting in the number 2 spot of the action bar. It seems you have linked the num keys to the row of numbers.
I kept wondering why every time I was opening my inventory I was getting a healing effect.
Heads Up: When in the chat screen you can trigger some hotkey affects. One in particular End Turn, you have that say to "E", every time in combat while chatting and you enter an "E" you just skipped a turn. I call this Nightmare Difficulty btw.