Worried & in pain

So this morning I had my first cervical check + GBS swab. I am 35 + 4 due 12/13. The doctor said I’m slightly dilated - less than 1 cm but 50% effaced, which her words were “shocking for a first pregnancy with no health problems”. She also said I’m measuring very ahead- 40 weeks to be exact. This was the first appointment where I’ve measured this big- my last appt was two weeks ago at 33 weeks and I was measuring 33.5. She ordered a growth ultrasound for tomorrow but my insurance denied it so now I have to appeal with them before I can get the scan done (thanks USA!!) but anyway...

I went to work after my appointment this morning and about two hours after arriving I started having unbearable pains. I have been having light cramping and Braxton hicks on and off for a couple weeks but today it was excruciating. I could barely move - I was doubled over at my desk and couldn’t focus on anything. I drank a bottle of water and tried eating but immediately felt nauseous. This went on for over an hour - I was having trouble timing anything because the pain was so constant I couldnt tell when they were stopping or starting. After more than an hour I called my doctor.

She said she would “highly doubt” I was in labor since she had just checked me that morning and “everything was mostly closed up” - told me it was possible the exam irritated me and told me to go home, take a warm bath and drink water and if the contractions worsened or became five minutes in length five minutes apart to call back.

As soon as I got home, I started vomiting like crazy. It was mostly liquid - think from all the water I had been drinking. When I was able to stop throwing up I got in the bath and contractions continued - I started timing them and they were a little less than 2 minutes each about 7 minutes apart. This went on for hours - they only just started slowing down - now I’m at about 30 seconds each 12 minutes apart and completely confined to my bed as it hurts to walk around.

Also forgot to mention I am having some brownish spotting my dr thinks is from the gbs test.

Has this happened to anyone? Am I going into labor soon?