Please Help. My daily life. please help.

I am suffering since three years. I feel fatigued throughout the day and have severe dyspnea. I get severe headache in morning too. My resting heart rate is around 100-110 and gets till 180-200 with just a flight of stairs. My weight is normal so I don't understand what is happening. I used to pre hypertensive with 137/91 and then was prescribed Inderal la 20 which I ate in July, August last year and after that my BP is usually 95/83 or 100/85 in that range (in rest). Why is the pulse pressure so low now! I was diagnosed with allergic rhinitis and allergic bronchitis in Jan this year and have been eating mondeslor for two months but I don't see any improvement. I did a pft, ecg and echo and they came out normal. I don't understand at all. I don't have any anxiety issues and I am pretty calm person. I am suffering from headache and breathlessness and it's affecting my daily life. Please help.