I understand that. It's easy to feel that way when you get weird looks when you say "VHS" and the 18-20 year old behind the counter thinks you are speaking a strange new language. Hell got asked what in the world NES meant by someone in a gaming store.
Plus sometime life can just make you feel old with everything you have been through.
I grew up with 8 track tapes and 45 records. No cable. Getting up to change channels....all that good stuff. Trust me, you're not old.
My birthday is next week. 45. That's only 5 years from 50.
My daughter is 20 and she remembers VHS tapes, btw. That's all she watched as a young child. Speaking of that, that is what makes you feel old. Your child being 20 years old!