I wouldn't necessarily put it off as dissociation. A lot of people 'snap' when they get angry, and feel like they have no control over their emotions/actions/thoughts etc. That is more an issue of emotion regulation. Of course, I'm just going off of the one incident you're talking about. Is it the same mood/thought patterns each time, or is it different? Are the actions similar, or the emotions, situation, etc?
I would definitely mention this to a doctor or counsellor. It would be pretty awful to come out of an 'episode' and realize you've done something hurtful that you can't fix.. If you're aware of your body doing this, it is your responsibility to try and get help for it so that it doesn't happen. I hope that you have someone you can talk to in person, and get support from!!