I also have A-fib. I wear an Apple Watch and it recorded my bpm at 161 at its worst. I was able to give the report to my cardiologist and am now being treated with a blood thinner.
There is a much less alternative to the watch Kardia Mobile. If I we you I would get one. I believe it is less than $100.
The monitor the doctor gives is extremely hit or miss. Mostly miss I think. Having your own device gives you control.
Let us know how you are doing!
Susan