is this normal

It is likely gas remaining from the procedure. during a colonoscopy they "inflate" your colon to make it easier to visualize and navigate. After the scope is done they try to get as much of the gas out as possible but they can't get it all out. That is why they tell you to try and fart while in recovery. You might try lying on your abdomen, or go from side to side, in attempts to get the gas moving. Don't try to hold in the urges to fart.

better to call and find out for sure than let your imagination take over with the worry. i've called a lot of times when i thought i was probably going to feel like a doof, but the relief of knowing something wasn't unusual or was expected was well worth it.

I always have alot of gas for the first day and am crampy for a couple days afterwards too. I think what your feeling is pretty normal. But if you are really concerned you can put a call into your doc and check with them.