You can get an ingrown toenail from wearing shoes that are too small. I have a cuticle infection so I recently googled discolored toenails, ha. Basically if it is an ingrown toenail they have to cut it and remove the ingrown part. I'd see a doctor. I had to see a doctor as well (that's how I found out it was a cuticle infection, the person who gave me a pedicure pushed em down too far), and he mentioned ingrown cause I was apparently cutting my toenails wrong.
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