Hello, here are the symptoms which have occurred over the last year. Always tired, swelling in my legs, dizzy, itchy back, nauseous, metal taste in my mouth, when I work out always trying to take in a lot of oxygen. Last year when giving blood they told me I had great results.....now, the last four time I could not give blood...numbers went from 125 to 122 to 120 last time was 117???