28 Y/o - Is Hair At My Crown Thinning?

Hey everyone! I'm 28 y/o and I recently noticed that the scalp at the crown of my head is quite visible. Unfortunately I don't really know how it's looked a few years ago, as I didn't really ever check that area with a mirror. I am WELL aware that it doesn't look as bad (yet) as what many other guys are going through, but I just wanted to hear opinions before it possibly gets worse!

Of course, on the photos I uploaded, I brushed my hair aside a little to make it more visible. I could brush my hair back a bit, so as to hide it. But that's just because my hair is quite long now. If I had shorter hair, I wouldn't be able to hide it I suppose. To me it looks, like the hair around the crown of my head is visibly thinner than it should/could be?

To me it was very surprising and shocking as none of my close family members has gone bald. Neither of my grandfathers and also not my dad or my maternal uncles (haven't got paternal ones). Of course, now that they're 50/60+ their hair has gotten a bit thinner and fewer, but none of them went bald and none of them has a bald spot on the crown of their head.

I also took pictures of my front hairline, as it seems perfectly normal to me and no sign of balding there. So do you guys think this thinning hair on top of my head is a sign of balding? Or could it also have been caused by something else, since none of my family seem to have problems with balding? Or am I just overly worried and it doesn't seem so bad after all?

Sorry for the long paragraphs.. any opinions are welcome, thank you! :)