Million dollar question

The million dollar question of the day is poop or dirt? I'm fairly certain I know the answer and it stinks. We were in a hurry to run errands in the morning before breakfast and nap time (he actually naps so I'm a little fanatic about keeping the morning nap consistent). He had a major downstairs movement before we left and since the changing table and his diapers must be lined with razor blades he lost his mind....there was kicking, squirming, and screaming (and possibly some frustrated tears and teeth grinding on my end). We wrap up and load up in the car. We go in and out of one store with no incident. I'm unhooking him to go into our second stop and notice a brown foot. It was dry and clearly had been like that for some time. I used a wipe to clean up and just keep telling myself it was dirt.....but we all know the truth, I brought my son out in public with poop foot.

Mother of the year. Life is clearly rough for this guy...