Maternal heart rate 48?

Edit: Yeah, I have an autonomic dysfunction where my blood pressure is always low, and drops when I stand up, making my heart rate constantly high. It's made pregnancy really complicated and I'm in a wheelchair a lot of the times. But, this time, my blood pressure was low AND my heart was barely beating. Stupid ER doctor just acted like I had a headache and ignored everything else. I'm actually switching OBs and have my first appointment next week because the one I have now is awful and acts like it's cool for my blood pressure to be 80/50 with a heart rate of 189 every time I stand, causing me to almost pass out every single day of my life. I can't take my normal medicine for my autonomic problem that raises my blood pressure. I normally take it 3X a day but it's unsafe during pregnancy. I just don't understand why my pulse was so low. That's the opposite of my health problems and I felt awful, like I was dying. 😭😭😭 I live in a tiny town and no one around here knows of or has ever heard of my problem. I have to go four hours away to a neurologist who treats me, but isn't a baby doctor.