Should I be concerned with numbness in my pinky finger, ring finger, and along that same line up my left arm? Is it a potential clot or a nerve issue?

Ulnar nerve. This sounds like a problem with your ulnar nerve up in your elbow. This is the thick cord in your elbow called your "funny bone" that sends electric shocks down when you hit it. You should get this checked out by a doc to see what treatment needs to be done before this leads to permanent problems.
Ulnar nerve. Numbness in the areas described can be due to pressure on the ulnar nerve. This can happen by leaning on the elbow persistently, for example, or trauma to the nerve. People with disorders such as diabetes may be more susceptible to nerve damage. If the symptoms persist there can also be weakness so it should be examined.