What Causes Shortness Of Breath Along With Tiredness Post Infusion Of Blood?

Hi what direction should I go in post hialt hernia repair I have been suffering with iron deficient anemis, I devloped allergic reaction to compount of IV iron so recieved 2 units of red packed cells. Two weeks following infusion short of breath, always tired, bruise easily, have hypothyroid and am on 100 mcq qd synthroid. I am 62 work 40-50 hours a week . Hematologist and internist said they did not know what to do for me. what should I do.