Did anyone else’s toddler who is almost two or is two start refusing milk ??? My son had a reaction…

Did anyone else’s toddler who is almost two or is two start refusing milk ??? My son had a reaction to milk once he turned one so he was put on lactose free only . So now we have tried regular milk again so far it was ok but the past two days he has become very picky about it, last night he didn’t want milk before bed . And today he went the whole day without anything , I tried offering milk heated up like he usually has and he handed it back to me then pointed to a water bottle. I gave him a sippy cup with water he went to sleep practically drank it all ! Idk what to do , I don’t want to start flavoring his milk but he loves other things with dairy (cheese , yogurt, ice cream ) so we shall see .