Fired because of pregnancy?

I missed 3 days of work last week because I got sick with my pregnancy and I almost passed out at work and had to leave. I got notes for all three days. I contacted my manager and told her my doctor was keeping me out until that Monday because I had to follow up with her that day. I was only supposed to work sun, mon and Tuesday, the only day I didn’t text her was Tuesday. And they didn’t have me on the schedule at all for last week, I texted her asking her when I could come in and she never responded and then I text her again and she says to call the store on monday(today) and she tells me since I missed 3 shifts with out calling that hr is gonna call and talk to me because they need dependable people and that they are basically gonna let me go because of it. I have all my doctors notes and also a restriction note on what I can and can’t do anymore on the job and I was gonna turn all those in the day I went back. Advice? I can’t stop crying because everything is falling apart. I was also supposed to start a second job this week but there system messed up for many people, including myself and now I’m having to reschedule my start date and my shift when me and my bf already had a plan set to work the same shift. I’m losing my mind here 28 weeks pregnant and my hormones are raging!