You mention your grandma having it. Did she recently pass?? My mom recently passed away and sometimes I feel “sympathy pains” from what she was experiencing.
As for worrying about dementia.....
Highly unlikely for you to develop it at your age. I’ve been struggling a lot lately wondering if I’m going “psychotic,” and I find that anxiety makes you reinforce every little thought and action to support your claim. Soooo if you do something, even ordinary, if somebody with dementia struggles with said doing then your anxiety will “reaffirm” that you’re developing / have dementia. It’s really a symptom of our illness to second guess & seek evidence for what we believe we are experiencing.