Periodic onset exhaustion with spurts of energy here and there?!

Hey ladies, second pregnancy here, I remember with my first I had terrible morning sickness and was exhausted my whole first trimester due to the horrible morning sickness but it let up as soon as I hit 13 weeks. This time around not as bad of morning sickness just nausea that comes and goes is anyone else experiencing this? Especially with a 2nd pregnancy.

**Also wanted to add will get onset full body exhaustion for a day or two, but then will have great energy for a few days too.