Idk what’s next

Has anyone been going through trouble at work? My boss is aware I’m pregnant and my morning sickness has been bad when i get it, it’s just not consistent. I had to call off last week cause it was so bad i couldn’t get off the floor. And his response was that he’s going to have to write me up and if i continue to call off 2 more times he’ll terminate me. Is there something i can do to protect me. I’m aware that i need to be at work and it’s not like i enjoy missing work but how am i supposed to get to work when i can’t even get off the floor or stop throwing up for a while? I contacted HR and i have a meeting set up next week but I’ve been coming to work the last 3 days basically spending my whole shift in the bathroom. What am i to do? I told the NP at my last appointment i had morning sickness but she just gave me natural remedies which it’s fine i guess. But it’s causing trouble at work.