Bystolic Fatigue and exercise

I hope this is in the right forum, if not, sorry but,

I'm about two weeks into taking a beta blocker for migraines. I'm on 10 mg of Bystolic a day and all I want to do is sleep. I have very little energy to do anything and haven't exercised in a while because of feeling so tired, needing extra sleep, and finding it so hard to get going.

Any one else have this issue? How long does it take for it to stop? Does forcing oneself to exercise even when yawing and junk help with energy levels or am I better resting until the fatigue levels out?

This has been a rather vexing issue for a bit now, so thanks for any help or advice.