I Am A 55 Year Female In Good Shape And

I am a 55 year female in good shape and in good health other than hypothyroidism that is treated with daily Levothyroxine 100 mcg. I got s virus and a bacteria that caused pneumonia and a collapsed lung after fainting that put me in the hospital 5 months ago. I was in A-fib but that went away prior to being released from hospital. I was put on Metropolol 25 mg. but I am gaining weight and want off. Can I just stop taking it. I wish I was off this soon after being released. I'm miserable.