Pregnant Body Shaming

Okay first things first...I work at a preschool. 
I'm in my third trimester. 
Today at work, I'm passing out snacks and my boss comes to the door. She calls me over and proceeds to tell me that from here on out I should not sit on the table or the preschool chairs because I'm getting bigger and I may cause the table to collapse. She told me that I should find another place to sit or they would look for me a chair (finally-I've been telling them I need to not continually be in my feet.) 
I politely told her that I usually sit on the stage in our room. And she replied that's great it can support your body and won't collapse. 
Then she tells my co-worker that it's become increasingly noticeable that I'm slowing down and that she's concerned that the job is either too much for me or that I'm slacking off and getting lazy. 
Seriously?! 
Did we forget that I'm growing a tiny human?! Maybe I'm just hormonal or too sensitive. But I was so taken back, embarrassed and insulted. 
My heart was so broken after that. And obviously other people heard it, which embarrassed me more (props to them for comforting me after). 
I wanted to cry, but I didn't want her to know she had gotten to me.