One way you can learn about yourself is to pay attention on how people react to your actions.
I have a "angry man resting face", which means that, even when I'm in a null mood, it looks like I'm angry.
I already had one meeting and which I started to ask something and noticed that the other person move a bit back. That's when I realized that didn't sound exactly how I meant. I had to add "I'm not saying what you're proposing is wrong, I'm just confused."
Also, I got a manager once come up with "I thought you were the serious person... till you suddenly started singing in the middle of a meeting"1.
You need to keep an eye on this. How is people reacting to your reactions? Are they opening themselves to you or are they closing?
I have this "serious" problem that, depending on the word someone says, I recall some lyrics and suddenly start singing it.