Try not to actually use words such as angry, happy or scared. Focus more on what is happening to the characters, their physical, emotional and mental reaction. "Show don't Tell" if you will.
For example:
I heard the footsteps in the corridor and became very frightened.
BORING ALERT!
Let's try something else:
I heard the footsteps echoing in the corridor and fear took over me as I sat there paralysed.
Hm, not bad, but there is still that word that TELLS the reader the character's emotions.
Now let's try not to do that:
I heard the footsteps echoing ominously in the corridor as I sat there paralysed. Every muscle in my body trapped in a trance and sweat building up on my forehead as the footsteps came closer and closer.
See, that's more like it. The reader isn't being directly told that the character is afraid but they can deduce that from the character's reaction.
I'm sorry if this is late, but I just thought I'd put this out there because I've been in a place where you can't describe emotions very well before, so I feel like I can give quite sound advice on this topic.
Hope this helped you.
