Is my husband hiding something from me?

My husband works out of town all the time and is not a drinker or smoker. But the other day he called me sounding real out of it and i know its not alcohol because he is a recovering abusive alcoholic so any kind would have set him off on me. But he was nice and kept telling me that he would never cheat on me and that i should trust him. I dont know what to think, any kind of answers would really help on this moment. Im thinking of just acting like nothing happened and letting him come clean with me instead of confronting him.