a weak spot

There is a dent in the part of my skull where my hair line meets with the skin of my forehead. The dent is vertical and goes all the way down my forehead to my brow line. i wonder where it came from.

seems like a long time ago i hid under a bed. someone jumped on the bed while i was under it and the bed when through the floor but i didn't. The result was that my forehead was mildly crushed. It left a gash and a bruise.

yes, he knew i was there. And yes it was intentional. The bed going through the floor however was an accident. so i can't be mad.

The point is, the gash i got in my forehead from that was lower than the one that meets my hairline and it was also a horizontal dent, not a vertical one. So they would have made a cross in my forehead, except that the gash isn't there anymore.

is this a normal place for dents? Do you think this is a seam in my skull. From when i was an embryo forming into a human being and my skull fused together at this point.