I take 2.5 mg of bisoprolol every morning. It help with my pvc's. I have over 35 000 of them per days.
You didn't mention what drugs you are taking, but drugs in the beta blocker class commonly can drop blood pressure to the levels you are experiencing, especially when you sleep or rest. Until the cause is resolved, I'd suggest before standing up from bedrest, sit on the side of the bed for perhaps 15 seconds, and *slooooowly* stand. I state this from experience, I passed out several times, once with rather dire consequences. In my case, I had to have a pacemaker inserted.
Keep us informed.
No that pressure is too low, you need to report this to a Doctor asap. If you can't get an urgent appointment, I would go to the hospital. There could be some underlying problem causing this.