Found a bra and not sure what to do

So I found a bra that I do not recognize in my dresser. My first thought is he's cheating. My husband did cheat on me 6 years ago but we were both 16 at the time. There is a possibility that it's mine because I had gotten a bunch of donated clothes from a church a month ago that including pants, shirts, dresses, bras. I hadn't actually looked through most of them so my husband had just washed them and organized everything. So it COULD be mine, but idk. What would you do in my situation.