Hair loss or maturing hair line?

[Repentance]

Hey guys, Recently been noticing a change in my hairline in the past few years, since i finished high school (18) i am now 21. my dad does have a receding hairline and does still have hair, just not at the front, no loss of hair on the crown or any where else. just the front. my mothers dad does not have this condition. and my mentor which lost his hair at 25 ish said it is nothing to worry about. should i be? or is it nothing and just a maturing hairline?
p.s. always had thin hair and no thinning at the back