Thanks for query.As per your history,you might be suffering from.postinflammatory hyperpigmentation.Difficult to comment without seeing the actual pictures.
Next Steps
Avoid the hairdye which caused the reaction as you.might be allergic to the component present in that hairdye.
Health Tips
Dont apply any potent steroid creams on face as the facial skin is sensitive and that may lead to other issues.You can consult me @ practo direct for appropriate treatment.