Many interests = Shallow person?

I have a lot of different interests & hobbies. My habit is to go full steam ahead on one hobby at a time for a few days or weeks, and then move on to something else. For example, I was obsessed with Sudoku puzzles for a time last year. I would work on them all day sometimes. Now I never do them at all. I also did watercolor paintings last year for a couple of months. I'll post one here.
I like fishing, camping (including backpacking), cooking, reading, writing poetry, and singing in the church choir. I also do "crafts" - mainly paper crafts and drawings now, but I built a dollhouse with mostly handmade furnishings a few years back.

The choral singing seems to be more than a passing interest, I have been doing it for six or seven years. I don't really have a soloist-quality voice, but I read and recall music quite well and have accurate pitch. Music is something that I can carry around with me in my mind and enjoy all day long. I love the challenge of mastering a new and difficult piece, and being able to hear it in my head, whenever I choose.

Sometimes I wonder if I have ADHD or obsessive-compulsive disorder. When I take up some new hobby I can hardly think of anything else sometimes. I have always managed to go to work every day & earn a living, but my mind is usually not concentrated on my work. So, do many interests make me a shallow person, or what?