EXTREME fatigue 5 & 6 DPO...

Starting yesterday I have been way more tired than usual. Yesterday I took 2 naps, one was 2 hours long. Usually if I nap during the day I can’t sleep at night but I was out like a light at 10pm! Today (6 DPO) I took another 2 hour nap. I tried to fight it but I couldn’t do anything at all or get any work done so I caved. Even after I forced myself to wake up I still feel like I can sleep until tomorrow morning! Can this be a early sign?