It sounds like your AFib symptoms are severe and you should consult a electrical specialist, and EP as already noted. That could lead to an additional attempt to convert you with medications and/or electrocardioversion. Electrocardioversion no longer work for me, they did in the past, I have 15 years history of AFib. I am in permanent AFib, so I don't have ups/downs, it is constant. On the good side, I don't even notice it unless I want to do more than walk on the level. That is I can no longer jog for exercise.
There are many options and you should explore tham all.
Have you seen an electrophysiologist, a doc who takes care of the electrical system of the heart?
ksig