I really hate to mention this,,,,,but sometimes when using the tapping type plug the darn nut welded to the inside of the pan breaks loose and spins before it gets tapped out all the way by the new self threading plug.
Then the pan has to come back off anyway to get fixed.
Here's hoping your does not.
In any case start that self tapping plug in there as straight as possible.
I hate oil leaks and seaps with a passion, so I always put a small bead of silicone seal around the plug threads right up against the head of the plug before I put them in.
Keeps them bone dry.