Came back home to find a Condom packet I'm trash. Husband says "he has no idea"

I was at the dentist for 4 hour root canal. Once back, I was putting my son to sleep and then I noticed a torn/open condom packet in the trash. It was at the top. Meaning must have been thrown recently. So I asked him casually that where did this come from since we havent used condom in a while. So he jokes and says" I have no idea but i want to know what are you imagining?". I obviously at this point is getting irritated because he is not taking me seriously. So I ask him again and again. He finally says that why am I making it a big deal and that he has no idea. And gets upset because I doubt him. There is 4 of is in house..we 2 our baby and my son. There is no other person who could use it or trash it after. We didnt have any guests except caregiver for my son. I didn't want to go after my upset husband because I want him to realise that I still dont have an answer. Should I be doubting him? Or am I over reacting?