Part of tooth still in gums after surgery

Hi, a few months ago (February) I had oral surgery to remove a bad back right tooth. It seemed to go well.

Now, I am noticing that in that same area, there is a bulge outward in the gum where a piece of tooth that wasn't removed is still there. There is a very, very small part of it that is even sticking out. I don't know how long its been there, since I haven't noticed it till now.

What should I do about this? Go back to the dentist? Thanks in advance.