If you are resting (not exerting yourself) that pulse rate is good. Usually when a problem is serious, the heart rate
increases. In which case, you need to be seen by a doctor right away. If you can't catch your breath, call 911.
Otherwise, I suggest you call your local hospital and ask to speak to an advise nurse. Just tell her about your breathing problem and she will tell you if she thinks you need to be seen by a doctor tonight.
Or call an emergency room and ask to speak to an RN (nurse) and talk to her.
Otherwise, make an appointment with your doctor.