I am sorry to hear of your worries. 12 weeks out is such a short time to evaluate anything, your heart is still settling down and healing the burns on your heart. I can't say you will wake up one morning and the beats are gone. It is more like you slowly experience more and more good days in a row than bad.
Some Drs. may put you on Atenolol. Do check in with your Dr. to get a professional opinion.
Rest up and try to understand that this process takes time, a lot of it!
I hope this relieves some of your worries.