Pregnant and my job..

I found out i was pregnant 2 days after I came back to work from being laid off..

I then told my boss I was 2 weeks after because I got morning sickness i was again laid off because my dr wrote out orders for accommodation and that took like 2 months as I work for a casino.

I've been at said job 1 year and 4 months i also had a shift bid for day time and im also 6th on senority list, so they call me back a few days ago and tell me i can come back i was like ok good but they put me on night shift!!!!!! I asked them why they said that's all they had and that if i didn't take it id be fired. My morning sickness is worse at night and there's a big difference from customers from day and night i also feel like the hard work ive provided meant nothing and this was a slap in the face the person who got my positon has been with company for 2 months...... im just really upset i have to go into work tonight and I just really don't want to go i feel like using my FMLA im just really depressed and unhappy I have a 2 year old which I dont have a sitter for she will have to sit at my husbands job for 3 hours until hes off they made me change my life in 3 days that I've had set for 1 year and 4 months in the middle of coronavirus... :(