Adderall, Heart Rate, and Beta Blockers

I started on Adderall a little over 6 months ago.  I take wellbutrin also along with provara for hormone imbalance.  At my recent check-up with my prescribing doctor, she noticed I had a fast heart beat (in the 90's).  I wore a heart monitor for a day got the results today.  It showed that everything is normal but I do have a very fast heart rate throughout the day.  The nurse said that the md wanted to put me on beta blockers.  I have to say, I HATE taking medication but do so for the sake of my family.  I am so scared to start on something that affects my heart.  I do not have high blood pressure.  In fact, I have always been told that I have very good blood pressure.  I don't want beta blockers to screw that up.  Also, I'm not sure of the logic behind taking a stimulant to get me moving and then taking a beta blocker to slow me down.

I've read a few places that Adderall can cause a rapid heart rate.  I'm wondering if anyone else has this problem and what they did about it. 

Some of my other side affects include dizziness and shortness of breath. 

Any insight, no matter how small would be helpful.