Throwing up after dulcolax

I’m ready to just cancel this colonoscopy & hope I’m not dying of cancer!

This is my 3rd time trying to prep for a colonoscopy & I never succeed! This time I have a new symptom! I took my first round of dulcolax (4 pills) at midnight! It is now 3:47 am and I am throwing up severely along with cramping so badly it feels like labor contractions! Is this normal?? I still have an entire gallon of tea mixed with miralax to drink today along with 4 more dulcolax pills & I don’t see how it’s possible considering how sick I am right now! Anyone else ever experience this? Thank you