Early labor?

EDIT: I went to my OB ER I should’ve clarified as I know this is not normal for every hospital.

I am almost 21 weeks and since about 6:30 last night I have had extremely excruciating abdominal pain that has gotten worse. I went to the ER around 10 and all they really did for me was check my cervix said my cervix looked fine and sent me home. I have been trying to get comfortable enough for hours to try and get some sleep but I just hurt so bad. My back hurts, my abdomen hurts, gets worse if I even move the slightest bit. I’ve been trying to go to the bathroom because there is so much pressure like that is maybe the issue but it never resolves it and just makes me feel worse. I had to call out of work as I’m a CNA and literally could not be doing my job right now feeling like this and I’m just really scared to do anything right now. I have hyperemesis and I’m also at risk for preeclampsia and my blood pressure was high in the ER but being in pain I expected that. I don’t know what to do. It’s been almost 12 hours of this.