heart palpitations won't go away!

A few days ago I started having heart palpitations that wouldn't go away. I went to the doctors about it and got an ECG done, apparently everything is fine it's just what happens to some people in their 3rd trimester of pregnancy ( I'm 30 weeks). i have had palpitations before but they were never consistent like this and it's really annyoing. does anyone have any tips of how to deal with it? Maybe stop them or have it happen less, it seems to be happening every 5 minutes all day every day now.