Toddler ate old French fry

So when getting home today, I had saw my two-year-old son eating something, I immediately got it out of his mouth. It was an old French french fry he must’ve somehow found it in his car seat. It was a six day old french fry from In-N-Out, I took as much out of his mouth as I could. I think he only ate a bite maybe two. The fry was completely dried out. I’m still worried about the bacteria risk , should I bring him to pediatrician or just monitor ? I feel terrible