Battling exhaustion

I am 5+4 and among all of the symptoms of nausea, bloating and sore boobs, exhaustion takes the cake. I struggle getting out of bed after sleeping 9 hours, and I can hardly keep my eyes open while I'm at work. I get home and just feel like I've ran a marathon. I've cut my coffee intake way down to 1/2-1 cup a day and do not consume any caffeine otherwise. I'm also taking a daily prenatal. Does anyone have any suggestions on how I can better deal with this? Any vitamins I can supplement? I don't want to be this bump on a log anymore!