Is it just the nature of the beast?

Where is the fine line of just being stressed out and having something wrong with you? I really think it is stress, just need some reassurance.

Forgetful yes
Scattered yes
Staring at something, you have seen a hundred times and can't remember what it's for yes
Brain MRI in Oct 04 good
Weight loss yes
Headaches yes, but nothing new
not sleeping yes
stressed yes
vision problems no, actually vision seems better except for small print.