Honestly, I'd let it go. It sucks and she was unpofessional and you're feeling the heat of the moment (did she ever claim to BE a professional?). I think if you were to do anything right now it would just seem malicious.

I'm not sure there's anything positive that you can do to mend the situation (other than express your frustrations with her behaviour to her...and really, I don't think she'd really care right now). You could tell others who ask you that you weren't happy/un-impressed with your daycare provider.

Is she certified or in any way tied to an organization (sometimes the city will acknowlege certified in-home care centres and offer subsity to their programs). Unless she is, I think you can only vent.

Sorry it's been a bad experience. DS was an agressive tot and what he really needed was lots of patience and guidance (to him it made perfect sense to hit someone to say 'hi'...it took lots of rehersing and practicing more acceptable ways of initiating play). It's probably for the best that she made the change for you. Obviously she couldn't handle the situation properly, so it's probably best your DS is out of that environment. Be happy you found other care so quickly. Hopefully the change will do you both some good.