Been with my fiance for 3 years and we are expecting our first baby together. We have never used condoms the whole time we've been together but yesterday I found a condom in his book bag he carries to work. He doesn't work with any females and seemed really sincere about not knowing where it came from but it seriously freaked me out. He used to lie a lot in the beginning of our relationship but hasn't lied or done anything questionable in a very long time. Am I in the right for being upset about this mystery condom or could there possibly be another explanation.

Would you be upset yes or no and please give me some words of advice.

Thank you ladies for taking the time to help me out on this matter.