Hello and thank you for using HCM. I carefully read your question and I understand your concern. I will try to explain you something and give you my opinion. A person might experience fast heart beats for different rhythm issues. If his heart beats in a regular way, over 100 beat for minute we are talking about sinus tachycardia. It might happen for different reasons from simple emotional stress to pathologyes like anemia, hyperthyroidism ect. Sometimes, in young ages, it is quite normal. We expect that his heart rate might go up to 220 minus his age. Fluctuations of frequencies between 90 to 105 beat for minute in a distance time of 5 minutes are quite normal, if the rhythm is regular. There are some other king of arytmias, like supra-ventricular tachycardia that begins in a sudden way, the heart beats over 100 beat for minute and it suddenly stop and goes back to normal values immediatly. Fluctuations of blood pressure with a difference of 10 mm Hg(132-120) are quite normal, they are not a pathology. It is difficult to say what are this just depending on symptoms. If i was your treating doctor I will recommend a holter rhythm monitoring to evaluate rhythm tendency and a simple chek up with blood sample, thyroid hormones, echo-cardiogram. After this we would have a better view. Sometimes this are quite normal at this age. Hope I was helpful. Best regards.