Thank you for reassuring me... I feel bad about complaining about this as he's only a toddler and didn't really physically hurt me. But on an emotional level I was a complete mess afterwards.
You reminded me of something my T told me once: "Don't take this wrong, but you're family is absolutely crazy!" I guess she was right...

And yes, removing myself from the scene by going to my room may be a good option. Will try it next time.