Feelings and Moods

To feel

You can use this verb to talk about how do you (or someone else) are feeling.

Mood

You can use this to talk about how do you (or someone else) are feeling. But if you are talking about mood you have to use the verb "estar" cause it is only for an specific moment

Personality 

You can use this to talk about how do you (or someone else) are. In this case you have to use the verb "ser" cause you're talking about the essence of the person and not only about something temporary