I hate the way I (and maybe you) assume that if you’re over 70 (or maybe 50) every tiny temporary slip of the memory is due to incipient dementia and old age.
Senior moment? Never say it, write it or think it.
Forgot why you went into the kitchen? That’s just your lovely brain doing the right thing, segmenting and categorising tasks and working at maximum efficiency.
On the other hand, every threshold you cross is a good moment for a moment of mindfulness. But relax. It’ll all work out.