Taking bowel prep for colonoscopy - love support as I go through it!

This isn’t a question but rather a reach out for support.
I’ve started taking the bowel prep after many tears and now just waiting for the laxatives to work.
I have the worst headache but I have been drinking heaps of water!
Drinking water and apple cider vinegar, I also have Gatorade and barley sugars. I’m really freaking out about fainting and pain!!?

Anyone going or gone through it want to chat??