You can't screw up your emotions or expressing them; they are what they are. Untangling and expressing them well though takes learning, practice, and a lot of trial and error, etc. to get them how you want.

There are a zillion shades of emotions, they are usually a continuum. "Frustration" for example, is on the anger continuum but when one realizes one feels it and expresses that, it can forestall the so-angry-I-burst-into-tears response (been there, done that). It is the bottling up and not saying anything for so long that makes it impossible to "get-there-from-here".

I still remember paying several hundred dollars when I couldn't afford it for my car repairs only to go to the car to drive away and it was exactly as I'd left it that morning (switches pulled out/wires showing and everything) when I dropped it off; they hadn't touched it. My best friend was with me, had driven me to the repair shop but she had to get somewhere else, was late for what she was doing; I burst into tears and she had to explain to the shop manager what the problem was. My only other recourse felt like killing everyone?

40 years later now, after a lot of good psychotherapy, I could deal with that, get the problem solved better and with less emotional cost to myself.