Tiger, i wouldn't say you aren't a musician. You've done pretty well with that mandolin. It's a big step to learn another instrument. What, you play 4 different ones--(guitar, mandolin, piano and i heard you mention fiddle?) You don't have to know all the players, just what you play. You are a musician whether you like it or not. Just like when you raced, you were a runner.
I like to call myself a student musician. At some time period, i'll graduate. Though i'm not sure this is possible, Fretmentor says it's a life long journey.