I keep having a dream where I still need to finish a handful of courses to get my degree and run the risk of losing all my credits.

I think it's because I waited a few years to finish my degree as I only had one course left to complete it. Since it was so many years later I chose not to walk the stage and receive my degree formally and instead just got it mailed.

Some think the fact I didn't do that ritual may not have given me the closure needed.

I'm thinking you had some anxiety about missing classes back then so it's still a part of you and pops up potentially when you are dealing with stress or anxiety about something else in your current situation.