Do I need a root c, or a normal filling?

The dentist will have to take an x-ray of the tooth and do some other tests to determine if a root c is needed. Just from your description, my guess is that you probably do not need a root c done, and the correction of your problem would be simpler. And if a root c is needed, don't let some of the bad things scare you. I have performed well over a thousand in my career and have had a couple done on myself, so I speak from experience. Good luck.