Is my ef getting worse???

a year ago befor I was diagnosed with dil.cardiomyoathy I couldnt even walk a flight of stairs but since my meds i have been feeling really good for about 3 months but a few nights ago my blood has been up and down but still feeling pretty good, but today when I was vacuming it felt like I was being smothered,it was hard to breath and I started dripping with sweat then when I sat down I could see the pulse pressure in my eyes, my blood pressue was good, it was exactly the way I felt before I started taking my beta blockers a year ago,  does this mean my ef or my cardiomyopathy is getting worse? Or should I just not worry?