MIL issue

Last night his mother walks up to me as I'm cleaning the kitchen after making dinner and hands me a broom saying "this is your job, if you can handle it" I put the broom against the counter to finish the dishes. Went to move and she grabs me by the arms and says I'm not going anywhere. She proceeds to block me. My fiancé gets made and starts yelling. This is the start of a downhill spiral for the night. 

Now she is saying she never touched me and I need to be more respectful and stop lying about stuff. I told my fiancé she's not allowed at our place when we get one and i don't want her around the kids. Am I over reacting?