Hi There,
Please don’t be freaked by your lack of energy. That’s totally normal in your first trimester of pregnancy. I felt the exact same way (I’m at 20 weeks now) and it gets better, way better.
Your body is going through some amazing changes right now and rest may be exactly what you need so don’t fight it. I went on vacation right at 12 weeks and it was within days, literally, of going into my 2nd trimester that I felt more like "me" and had a blast.
If your Dr. has said that everything is normal and okay, rest while you can and take some "you time" to bond with your baby and your changing body. Hope this helps a little…