I have very high blood pressure. I was on a beta blocker for yea...

I have very high blood pressure. I was on a beta blocker for years (my heart runs extremely fast) to slow the heart down. Too many side effects - asked the doctor to change. First of all NEVER go off of a beta blocker cold turkey (yuk). Anyway, my heart is really fast (I am on 240 mg). It seems that my heart still is running extremely fast and I have developed the most horrible pain in both of my arms. It is from my elbows down to my fingertips. It feels like someone is squeezing my arm really tight. My fingers are tingly. Is this a possible side effect or has anybody ever experienced this before?????