I'm going to dump out my friend's orange juice after he threw it at me
He threw it at you? How are you feeling right now?
Like I'm in a very bad mood
It's fine to stand up for yourself. Otherwise people could start taking advantage of you. However, you shouldn't waste the orange juice, and you should talk to your friend about his behavior.
I don't like their behaviour. I felt like he was trying to bring me down or something.
He may have been, but it would be best to take some time off to cool down. Confronting someone when angry could be dangerous or lead to harming the relationship.