Every new to me vehicle gets an oil change after a hundred or so miles for that very reason. There usually seems to be some metal fillings that end up in the first oil change.
When I took my GMC 2500 Denali in to get one of my "free" oil changes, the tech told me that I wasn't thinking of the environment by changing the oil in a diesel after only 2500 miles. I told him that I was way more worried about my engine than I was about the environmental damage.
End of that conversation!