I am a brittle asthmatic with iron-deficiency anaemia. ferritin is 4, and my haemoglobin is 9.7. today, my resting heart rate is 150bpm. see a doctor?

See your MD: You may have an increased heart rate from some of your asthma medications--though not mentioned, I presume you are on some bronchodilator meds which can raise your heart rate. Prednisone should not raise your heart rate. Anemia can also be associated with increased heart rate. See your MD to get checked out and give you some peace.