Oh no, I do not suggest you pull the "what are we" talk, heavens NO!!Men are told not to ask “what are we” though. Makes us look weak and needy. And I’m not about to be exclusive with anyone I’ve only been out with 4-5 times. One of the girls, we even had the “what are we” talk and we were both on the same page. Then not two weeks later she pulls the “my ex called me yesterday” crap.
If you feel you are not ready to be exclusive, then don't react to her manipulative games and don't ask to be exclusive, or otherwise ask "what are we?" or "where do you envision this going?" or the like.
Simply stay true to your own core, your own values and if she is into you, she will comply, 100% TRUTH.
It all boils down to whether or not she values you and your relationship (up to that point) and she is truly into you.
Again no women is going to leave a man she is truly into (assuming you are treating her well and with respect) because you are not yet ready to be exclusive after only a few weeks, and I speak from experience when saying that.