Hello and thank you for using HCM.I carefully read your question and I understand your concern . You should not worry about . I will try to explain you something and give you my opinion. You should know that normal heart beats range between 50-100 beat for minute. If the heart beats over 100 for minute in a regular way than we talk about sinus tachycardia. Sinus tachycardia might happen for different reasons like simple emotional stress, coffee and energy drinks consumption or pathologys like anemia, hyperthyroidism, electrolyte imbalances , active infections. A flu or a bacterial infection might be responsible for sinus tachycardia becouse during infection our imunitare sistem is activated and the hole organism needs more supply so the heart goes on tachycardia. Other symtoms like headache, muscle aches and dizziness are normal, they soon will dissappear. So, dont worry, it will pass. Hope I was helpfull. Best regards, Dr.Ervina.