In formal writing, is the following usage of punctuations acceptable?
I keep asking myself. Who am I? Where am I from? And where am I going?
I'm not quite sure whether using a period after I keep asking myself is weird. To me, the natural choice would have been a colon, but this also would have made the first interrogative sentence have to start with a lower case w whereas subsequent ones, as they follow a question mark, must begin with a capitalised W , like ..asking myself: who am I? Where am I from..., which doesn't make much sense to me either.
Of course, alternatively, I can reorganise these interrogative sentences into clauses like
I keep asking myself: who I am, where I am from and where I am going.
But this feels much less emotionally charged than the first one, which makes it not so desirable to me.