I retired almost 5 years ago and was exhausted and worn out at the time. I was driving about 2 1/2 hours each day. I rested for a couple of weeks and jumped into a very busy schedule. I was involved in so many groups and doing all kinds of projects. Over the last 6 mos. or so, I had to force myself to do anything or get anything done. I had reached a point where I didn't even feel strong enough to drive. I finally realized it may be my thyroid and started homeopathic therapy for it about 3 weeks ago. Also have always been anemic over the course of my life and am taking iron supplement as well. Within the last 2 weeks have I started feeling like my old self when I could get up early and stay up late and get many things accomplished. Still not totally back where I need to be but am looking forward to get back totally!!
Hopefully you are just in a "slump" and no other problems going on. But if it lingers, don't wait like I did and thought it was a part of just getting older. Go for a checkup!!! God bless...