anyone know why my baking is getting weird on the edges?
Looks like your cage is catching the bricks above and below it. Either don't make the cage so big or space out the bricks before you bake them and then reassemble them later. I'd also say as an aside you should consider looking up how to space out your UVs properly for next time to get a good bake, even with the other bricks you could make them look better. The short version is that you want to make sure that where there are hard edges your UV islands are spaced out slightly to make sure you don't get seams like you have. I'm not good at explaining it so just take it as advice to maybe look up the theory.