A Colonoscopy is VERY important!! So glad you have made the decision to get one.
Who to call? Depends upon your insurance. You can call your provider and find out if you need a referral to a gastroenterologist - the doctor who typically does the colonoscopy. If you do - find a PCP in your area and go do the normal physical exam and then get the referral for the colonoscopy.
IT SHOULD be covered. All depends upon your insurance.
It's outpatient. If they find polyps, it might take a few hours. You are put in twilight sleep and put in a chair afterwards. It was 3 hours from check in to leaving for me.
You do NOT go back to work that day. You will be groggy.
The prep is kinda yucky - but it's a good thing - I lost 4 lbs in water weight when I did mine.
Good luck! Hope they don't find anything!!