16 year olds and balding

I'm a year old guy with a low deficiancy of vitamin D. I've been experiencing this sort of "hair thinning for about 5 months now. I don't know if it's just me overreacting over this because I had the same hairline since 8th grade (the picture that is different from the rest is me when I was 13-14 years old.) I want to know if I'm losing hair and if so, any treatments for it. Thanks

Your hair looks fine! There is nothing to worry about.

Not balding, hair looks great, enjoy being 16 with a full head of hair.