There are other possibilities, most are not serious. My father had a growth in that spot for many years, and when he had surgery for his trigger finger they removed that too. Turned out to be a giant cell tumor. Still nothing serious but my mom thought he had made up the pathology result until she looked it up on the internet. 
If it bothers you then definitely get in to a doctor sooner, but the usual approach is wait and see and watch it --- until or unless it causes a lot of pain or interferes too much with movement.
If it bothers you then definitely get in to a doctor sooner, but the usual approach is wait and see and watch it --- until or unless it causes a lot of pain or interferes too much with movement.
