As a general rule, I try not to make Matthias "shout". When he starts to get to a boiling point, I try to have his speech bubbles in such a way that you interpret them as almost a whisper. But then again, a lot has happened over the past year-I mean couple weeks- that culminated in this day.
His first kiss went horribly wrong, he just had another violent encounter with his future mother-in-law, he has a headache, and these two crazy ladies won't stop arguing, and worst of all, he's falling behind on a project- which is one of the worst feelings ever-
So, yeah, I think he earned his loss of temper there.
I feel like "the bad temper" is definitely a common trait we see in a lot of especially love interests in fantasy stories- which is interesting to me. I don't know if that's what most ladies see growing up- and that's why people who tend to read those kinds of stories find it attractive on some level- or what.
But there's a thing to be said about anger- it's literally like fire- too much and out of control is absolutely devastating, but it's also the same kind of spirit that compels you to defend your loved ones against a wolf, bear, or murdering psychopath.