I had issues with color "correction" too. I think I fixed it; I'll know for sure when I post my next piece. Double check your working color space and your save and export color settings. Generally for digital and internet content, you'll want sRGB color space. When you post to DeviantART, the site probably converts your work to sRGB which causes the colors to be off. Instead of using "Export..." I now use "Save for web..." to ensure that the color profile of my work is set correctly so that it is consistent on all displays.
Fantastic adorable Pinkie Pie! Happy laughing Pinkie Pie is best Pinkie Pie!