for past two days I have difficulty taking in a deep breath - I only do so if I yawn. My heart is beating very fast with the least of exertion - just a few steps and my heart starts racing. I am 53yr old woman. I was sleeping last night and reached over my head just to open the window and my heart just started pounding so hard. When standing for a little bit I feel little pains in my chest and in my upper back...?
Get an ECG and examined by physician. Also check your thyroid hormones. What's IR blood. Pressure when u have palpitations?