You may want to take a look at this link.
Clumsy is far from the word I would have used here.
http://www.lewisandtompkins.com/library/objects-left-behind-in-the-bodies-of-surgery-patients.cfm
The other thing to keep in mind is that if you had a biopsy along with your colonoscopy, and it has only been two days, some pain will be expected.
My guess is that what came out was one of those separate finger covers. But if you saved it, look at it and see if there was (in essence) a finished edge, or if it looks somehow torn.
Do at least call your doctor or email him, for a record of what happened and to find out if they want you to come in for a further exam.
Well, it's sure clumsy practice. Some of those finger things are not part of a glove, they are just the finger. If that is what it was, as a practical matter, I don't think I'd sweat it much. But I would call the doctor's office and tell them what came out and what it looks like, and let them tell you if they want you to come back in for an X-ray or an MRI or an ultrasound.
I would start with the E.R. You probably have an infection. Not to mention the rest of the glove may still be inside of you. This is not a good situation.
I know the ER is not what most people want to do especially on a Friday. But I don't think you should wait.
As far as malpractice if you do not suffer long term effects from it I don't think you would have an easy time. I could be wrong. All states differ in their malpractice criteria. In Colorado any malpractice filings must go before a panel of both doctors and lawyers. Then they decide which cases warrant being brought to court. Over 25,000 cases went before this panel last year and only 100 were said to be filed. However you may want to save the finger of the glove and take it with you to the ER. And if they do find more of it have them save it or make sure its documented.