did i go too far

so yesterday i was at the park and saw my grandkids playing and they looked so happy, but then i noticed they had this new game where they use sticks to pretend like they re building something. it reminded me of when i was younger and how we used to do things for fun with whatever we could find around us. but as i watched them, i kind of started thinking about my own childhood memories more than being there for them right now. did anyone else ever get lost in the past like this while spending time with their grandkids? is it normal to feel that way sometimes?