You're off by about a factor of 10 in the number of years.

I think you might have misread Wikipedia: "given the false assumption of random mate choice without geographic barriers, the Identical Ancestors Point for all humans would be surprisingly recent, on the order of 5,000-15,000 years ago".

Also, just because you have the same ancestors it does not follow that you inherit equally from them. Hence Mitochondrial Eve and Y-chromosome Adam.