Woah.. I'm sorry, I don't do button braids, I do hunter braids. But, the bands you did were a little funny looking.. I found a video on youtube on how to do button braids that I thought looked good!
Also, never start from the withers up.. always start from the top of the neck, down to the withers. And, your braids will get bigger because the mane tends to get thicker in the middle. I think for button braids, you want them to be bigger anyway? I don't know, but that video looks great with a nice turnout!