Fatigue was one of my main symptoms (along with shortness of breath) before I was diagnosed and started on meds. Those still are the two that are the worst on my bad days.

I was late-pregnancy/post-partum when all of my symptoms really hit in the beginning, so everyone kept telling me it was because I had a toddler and new baby, and I should just take more naps.

But to me it felt like a very different type of fatigue and when I started going to doctors I made sure to explain it this way: I'm not tired. If I lay down I don't sleep for more than a few minutes, and I sleep just fine at night. It's more like full bodily fatigue where I just don't have energy anywhere in my body to make it get up and go. If I lay down for awhile I can recharge the battery to get a short burst to accomplish a little something when I do get up, but the battery drains quickly and I'm back to where I started.