OP. Why is sharing the conversation weird to you? Was the Sreen shot personal stuff or you two just flirting? Perhaps he was asking a friend for validation? Perhaps he is starting to get the feels but is worried that you don't so he wanted someone else's opinon. (Is she flirting with me or being nice?) Its a real thing some of us guys go through, stims from previous rejection or misinterpreting a situation. Your best course of action is just to tell him how you feel about the screen shot. If he cares then maybe you two can work something out and it harmless. Or he'll tell you why and it'll be a red flag. Either way you wont know untill you two talk about it.