From last 5 days,my heart rate is going high when i woke up around 105 -120 max ,rhen it will be under 80-100,but if i walk it will may go 100-110 again normal in resting position .my bp is normal ,no suger ,thyriod tablet m taking but its under control ,is it somthing else i need to chexk ,i did ecg its says only sinus tachycardia and dr saied its nothing to worry .my waight is 61 kg.i am a bit worrid still .please suggest.