Got fired for having weight restrictions

I started this job and was hired to eventually work full time. I did everything that was required of me. I finally got pregnant after a miscarriage in September. I've been having bad cramping like I did when I had a miscarriage. I missed a few days of work and 2 of which where I was in two different emergency rooms. The dr after my ultrasound told me everything looked ok at 6 weeks but I shouldnt be doing any heavy lifting or extreme workouts. Today my boss phoned me and fired me, she wouldn't give me a reason, but I'm pretty sure it's because she didn't want to accommodate my medical needs. I was in my probationary period, but isn't that discrimination? This is my first time ever being fired 😞