Hello carrerswitch,
You have a very interesting profile. I am going to give you the strong points:
Sport: professional swimmer, this looks good on your application, and it will help you!
Work experience: Successful own dental setup: that is a good point, you ll have to put the stress on it
Finally, I think you do have the perfect age for an MBA.
Keep in mind that Business schools like diversity, so you profile might fit.
However, your work experience is somewhat unusual, but I don't think it is a problem. You would have to make it clear, and to articulate elegantly your work experience with your entrepreneurial objectives.
Try, somewhat, to find leadership oriented features on your application, this is important.
Finally, I think your GMAT score is correct, but might be a handicap for BS such as Kellog. The decision wether to retake it or not belongs to you.
Let me know if you need more, and if this was helpfull.
Cheers
Experience: