Deliberate consent to sin despite having the knowledge of the severity of the sin.
Only you know if you committed a mortal sin. In your case though, anger comes suddenly and you might not have had full knowledge of your actions. Lack of full knowledge ==> not a mortal sin. Again, only you know your particular situation.
I assume that the anger kind of just “took hold of you” is that correct? In that case, its most likely a venial sin, especially since you said you only realized the sinfulness after committing the act.
Spontaneous anger, still a sin, but not a mortal sin.
See the above rules to make a sin mortal.
Doesn’t sound like it was mortal, especially as you had to think about it later, if it was mortal, you would have noticed it right away.
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