So tiny and cute ;33
Really beautiful! If you do another, I'd like to suggest keeping the overall blue tone but adding some small, diffuse areas of pink within the spiral arms. That would add another dimension of realism; spiral galaxies almost all have pink patches in the arms -- they're hydrogen clouds where new stars are being made. It's up to you, of course: this is your work and you're free to make it as realistic or imaginative as you see fit!