When did you start taking
Propranolol 20 mg? Side effects of
propranolol include abdominal cramps, diarrhea, constipation, fatigue, insomnia, nausea, depression, memory loss, fever, lightheadedness, slow heart rate, low blood pressure, cold extremities, sore throat, and shortness of breath( ref: http://www.medicinenet.com/propranolol/page2.htm). It is possible that your symptoms are related to the medication you are taking.