Thinning Hair At Corners Of Hair At 17?

[Dudewithhairandstuff]

For the last while I've been obsessing over the corners of my hair. I'm not sure if they are thinning. And I was looking for opinions. Here are some pictures. My hairline is not even an inch from my top wrinkle si I'm thinking maturing hairline but I'm not sure if hair thins before it matures.