We painted a white Linen color to touch up holes that were filled with drywall mud and the area turned pink even after it was dry, why?
I've seen before. You didn't mention sealing or priming the repaired areas before touching up. The problem could be the porosity of the drywall mud. When the spots are touched up the paint is soaking into the spots. This could cause the coloration.
Seal the areas with a shellac primer, 2 coats, then try touching up again.