Why is there so many hurdles to get over

I'm sat here trying to resist having an afternoon nap because I'm just tired of everything, tired of fighting (for the moment), just tired.

Why is it when I feel like I'm getting some things sorted, it just takes the tiniest thing to put me back. I had so many things I wanted to do before I'm 40, but now I'll just be thankful if I'm still functioning.

Maybe it's just the Monday blues, who knows, I just feel really emotional and wish I could cry instead of sleep but for some reason my body doesn't want to cry a lately, and I wish I knew why.

I've got so many things I want to do, and some that I need (must?) to do but no energy to jump the hurdles.

Surely it can't be the reduced dosage of medication taking effect already