I've heard the same as what V said, so I just wanted to add the link. We have great post about nodules on the site that may give you more information.
Rheumaotid nodules can shrink and disappear over time. They are usually hard "bumps" that form on the elbow, the underside of fingers, etc, and they usually do not hurt.
Thanks for this mine was obviously not one, it came up inside my leg, and went down in two weeks