These are not that bad! Especially for a first wedding, I'm impressed. Here are a few thoughts...
1) Too centered. I'd love to see the bride's dress going in the other direction and the couple being framed to the left to include more of the piano. Or keep the dress as is and frame them to the right. There is a chair to the left that is extremely distracting and I'm not a fan of those flowers, either. My eyes definitely go to the flowers before the couple. Putting the groom behind the bride like that is also a little strange, I would have had him stand a bit more to the brides right (left in the image).
2) If you had shuffled a bit to the right this shot would have been perfect. As it is, the groom is a little too hidden by the cake and you can't see the knife.
3 and 4) If you had shot 3 from 4s angle, it would be great. As it is now, the giant floating ball of flowers above their head is REALLY distracting. I'm spending too much time trying to figure out how this ball of flowers is floating like that and less time on the moment captured. But in image 4 those flowers are nicely framed and add to the image rather than take them away.
5) Good shot. Would love to not have his hand chopped in half, but that's the only thing that would bother me and it's a small thing.
6) Love the inclusion of the ceiling! Very nice! Only thing I would change is I would have shot wider and go their feet in the shot and pulled back a bit. But my personal pet peeve is cutting off feet in images and not everyone agrees with that.