Agreed. He sounds like he's nervous about the upcoming day and coping by dismissing your feelings. start a conversation that let's him express his fears, doubts, and concerns first. I often do this with my DH. Perhaps you're both feeling the same way, he just doesn't have a good way to express it to you.
Try to have a conversation with him, no yelling, and just letting him know how you are feeling and your concerns. Guys do freak out when the big day is only around the corner, but they should be there to support you as it is a big day for you too!! Sorry you are going through this and I hope he starts giving you the support you need.