For me, the worst symptoms have been related to my experience of severe haemolytic anaemia. When my haemoglobin was very low, I experienced constant breathlessness and tachycardia. I got chest pain as well and this had to be watched carefully as with the heart working so hard for so long, there was a substantial risk of heart attack. I was unable to so much as raise an arm for without my heart rate going up. I was unable to sit up or walk because I had so little blood that I'd faint if I tried. It was completely debilitating. I needed nurses for everything and couldn't even get up to go to the toilet. My urine also turned the colour of strong black espresso and I didn't smell pleasant either because dead red cells smell like a dead animal. I also turned yellow from the cell death too.