If someone is eating and that falls on the person by mistake, what will be a natural way to describe that? Actually a kid's eating and when he throws it on himself, his mom asks him to be more careful and the boy replies:
I threw it on myself, not you.
It fell on me, not you.
What sounds better #1 or #2? What would you use if neither of these sound natural?
Purely in terms of describing falls on the person by mistake, then I threw it would not be a good fit.
To say I threw it implies intention on the part of the person doing the throwing. If it's unintentional, then, between the two phrases, it fell on me is a better description—because it has no direct agent for the action.
Another way of expressing it could be I dropped it on myself by mistake. The addition of by mistake helps express the fact that it was an accident.
Note that dropped is a specific verb that by mistake works with. It would sound odd to say I threw it on myself by mistake. So, regardless of the additional wording, the verb throw isn't the right choice in this context.
