Why can't we use Past Perfect in the second clause of the sentence
'Did I tell you what happened to me?'
if the second clause happened before 'Did I tell you'
As far as I know, we use Past Perfect to say that something happened before another action in the past. Of course, sometimes we can use Simple Past instead when we have 'after', 'before' in the sentence and Past Perfect becomes optional there.
I googled 'Did I tell you what had happened to me?' in quotation marks and there was nothing on the Internet.
Could you, please, explain why we can't say that way?