If the coloring is under the icing (which it looks like some is, in the uniformly hazy parts), then it has bled possibly because you over-applied the coloring and/or the underlying icing was not dry all the way through. It could be a heavy application of coloring dissolved the top layer of the icing and bled into it, or a not-so-heavy application of coloring softened the already somewhat soft icing and did the same thing. I'd suggest drying your icing even longer and being less heavy-handed with the coloring. There is a little spotting in some of the areas, which suggests the coloring got too heavy before it dried and started to pool and separate, which leaves behind spots.
Additionally, there is a speckled halo around some of the patterns, which might be actual under-spray, and thus something that would wipe off with a brush. In other words, you might have both bleeding and under-spray going on.