Woah, am I being lazy or is that normal? Ever since week 4 I've been exhausted! I'm now only 5 weeks pregnant and I function OK from 7 am to about 2-3pm, but after that I just feel so tired

I can't seem to work out... All I wanna do is stay at home and sleep or rest/watch TV. I have no energy!
It feels very foreign to me because I used to train several times a week. I've always needed my 8 hours of sleep nightly but now it doesn't seem enough. I have a (private) dance lesson in 2 hours and I don't know how I'll make it. That's normal, right?! I sort of feel lazy/guilty. I wanted to take a dance class 1x a week in september but I don't think I will because I'm just too tired. I might drop in when I feel OK but otherwise I don't think I'll workout much during my first trimester. Please tell me this is normal?