Worrying about my dad...?

My dad turned 45 about a week ago and he had a bit of time off work and I have finished school now so I have been spending quite a bit of time with him recently and I was noticing that he has been forgetting things quite a lot. Its just small things like leaving the bathroom tap on upstairs and forgetting where he parked his car and just random things. I'm not sure if I'm just over thinking things because my mum works in a dementia home so I know a bit about it. And I never got the chance to meet my grandparents from my dad side so I don't know if anything runs in the family or something. Do you think this is something to worry about?