But you saying that you're not easy to live with is a total classic line of abuse victims. In this case (if that IS the case) it's not that a person is difficult to live with in general. They are probably perfectly fine and pleasant to live with, it's just that they don't fit into every whim and opinion of their abusive partner. The thing is that it's this expectation which is unreasonable/unrealistic, not the behaviour of the so-called "difficult to live with" person.
Also this: "I now feel scared to have another argument in case he does lose control."
Is not silly at all, you shouldn't get over it. Is he horrified by what he almost did? Is he leaving, seeking immediate help? No? Then he feels somewhat justified. You are right to be concerned. Please, please listen to your instincts and do not allow yourself to brush this off. The problem is that your immediate reaction will be "I wish this had never happened". If he goes back to normal (perhaps a slightly sweetened version of normal) then it will be very, very easy and extremely tempting to brush it off - your brain will want to gloss over it and pretend that it didn't happen, or that it didn't matter, or you misinterpreted what you saw. This is the very very worst thing you can do - if you don't want to end the relationship, at the very least you need to talk about it and acknowledge that it happened and why and how he can assure you that it won't happen again. If you can't do that, then you have your answer about the relationship.
Here comes the second point. Hardly anybody leaves after a dramatic or violent incident unless it is so extreme that police are involved. It's so easy to slip into this minimising/wishing and hence pretending that it never happened or it didn't count, kind of thing, and doubly, the longer you leave it to take action, the more you feel silly or embarrassed. "Well, I didn't say anything/leave/tell anyone at the time so I can't do it now, they'll wonder why I was fine with it all this time. I'll look silly. They might not believe me (etc)." If you decide, ultimately, to leave the relationship, and if this is a catalyst, it's fine if the time you decide this is six months in the future. It's okay to take time to process it and decide, some time later, that it was not okay. My previous paragraph describes some mental conditioning which is extremely difficult to fight and it comes from fear. Just don't let the double dip of fear happen, if you need to leave then leave, you don't need to wait for the "next" dramatic incident - it's likely that even if the "next incident" is more severe you'll engage in the same mental process anyway.
Good luck. Sorry I have written my post with certain assumptions.