Fiancé acting like Valentine's Day isn't coming up

Okay so I had asked my fiancé if he has any plans on Sunday, his response was no I don't believe so. So I had asked if we could see each other for a bit and he said yea that's not a problem. It kinda hurt me in a way because he probably doesn't even know what Sunday is. I know his spent it with his ex and had done things for her on that day so why's he acting like its nothing with me. I don't even know what to think right now. Should I remind him what Sunday is or what?