Unless you mean bruises I don't know why you used the word discoloration. It is simply coloration, and you should learn to love whatever color you were born with. You could use makeup.
Personally makeup just makes me even more self-conscious.
How can I remove the bluish black discoloration from my face?
Get a concealer, rub a red lipstick all around the dark spot and make it bigger in red than the spot itself. Lightly rub a bit or cornstarch on it and use a blush brush to smooth it down. Cover gently with concealer then use a liquid make up to even it all out