Hello doctor, from may last week I got sudden heart palpitations and breathlessness. If I do  walking (slow) or yoga or some other task heart rate would be around 150-170+.. after consulting with cardiologist took Inderal 10mg for 2 months still no improvement. So dr suggested to switch to betacap tr 40 and daxid 25mg. still issue remains, sometimes at rest also heart rate get  increases.. My cardiologist said stress would be the reason for this. I wanna a know when it will get fixed. 31year old female , breastfeeding. Ps:My ecg,echo,thyroid and sugar levels are normal. Using my iWatch to monitor my heart rate..how accurate is that? Or i need to buy any other monitoring device