Mine does the same thing, looks similar to my ekg's I have atrialfibrulation (sp), basically a irregular heartbeat but has the ability to backwash and that's what can mess you up..I.e. death, alot of it has to do with maintaining stress, heart rate, caffine intake etc. Im not saying that's what it is, just saying looks fairly similar to mine..I was diagnosed with it around 16 as well, not a big issue as long as you get the hang of controlling it