Note on HP. Someone's HP is meta information. You (as a person) do not know how much HP you have personally. You can look at someone and tell they are hurt, close to death, or uninjured, but to look at your friend and say oh he has 17 HP left is a completely obscure thing and you couldn't justify knowing.
We are still waiting on MP to show up to attack. Then the next round will begin. Talking between characters is not an action so if you have something to say to another character you can do so (it's part of role playing) if you want to try to formulate a plan of some sort