Need Advice!

So I just recently quit my job due to drama and harassment from the employees and the manager not doing anything about it. I'm 5 months pregnant and I've been having severe pain in my hips to the point I can't bend down without it being impossiable to get up and I stand 8 hours a day on top of that. I have a letter from my OBGYN saying I need to sit every 2-3 hours and eat due to this pain. I recently got told I needed to go scrub baseboards on my hands and knees with bleach... whatever I did it but had a hard time and got sent home 3 hours early because I couldn't just do it anymore. 
I quit today and the manager asked why and I told her and she said that my letter had nothing to do with me not being able to do cleaning duties 🤔 
I just need advice because some people say I can take them to court and others say I can't