When should I take maternity leave

I’m currently 8 months pregnant due the last week of April, I’m a high risk pregnancy. I have NST testing weekly, as well as lab work and ultrasounds. I’m trying so hard to keep pushing to work but I’m just mentally and physically so run down. I’m working everyday 8 plus hours on my feet non stop. I’m physically in pain every second I’m up and running around. I’ve been noticing as well that my coworkers are taking advantage of how hard I work and are sitting back chatting or doing paperwork when I’m on my feet the entire days, running around like a chicken with its head cut off because I have no help.

I brought up maternity leave with a resident doctor I saw today and he literally ignored my question and kept on going about the appointment so I just let it go. But I’m just wondering if I should call my normal doc and discuss with them. I don’t want my employer to be upset but I feel like I can’t do it anymore and my game plan was to work until birth but with my pregnancy now being high risk idk what to do!