Hi I have been to a doctor numerous times and had blood tests. They said there is nothing seriously wrong. For a while now I have been getting a pounding heartrate that just appears out of the blue. I do have asthma but ive had that for ages I know what that feels like. When I walk or get up my heart goes mad and I feel breathless . 5 weeks ago I ended up in a and e because I completely whited out. And even after that I was still collapsing, my heart was going fast, I was feeling dizzy and my legs were weak. They gave me antibiotics which helped a little. I expected to feel weak after that until I was 100%. After two and a half weeks off work I went back and after 6 days I ended up collapsing again after I got out the shower at noon and at work in the morning. It scared me. Then after a further 9 days I went down with sinusitus and an upper respirtory tract infection. Which even after two weeks of antibiotics has not cleared up. Also for some reason for the last 3 or 4 months my periods have been really irregular going from 2 weeks early to a week early then 3 days late now im 5 days late but ive always had them and they are quite draining and painful. Can u give me an insight to what this might be? Im getting really concerned.