I have intrusive thoughts with my ocd. I have no ability to diagnose you, but just can say what I've experienced. When I am fretting over something like you are (aging), it is usually part of my anxiety disorder. The incessant worry sounds a lot like anxiety. Often I become very fixated on an idea and worry myself silly about it.

Do you have a therapist you could talk to about all of this?

I hope you feel better. I worry I waste my time with my son too. Hopefully I won't look back and regret missing so much.