Why does my heart stop for a few seconds?

hi! I'm a healthy 15 year year old (going to be 16 in January) and for the past 5 years or so, my heart has been acting funny. About every month once or twice, when I'm relaxing, my heart will speed up for one second and then completely stop for about 2 and a half seconds to 3 seconds. It's really scary it feels like I'm getting a heart attack or something. Does anyone know what's wrong with me? Please help!

My boyfriend of 2 years broke up with me 5 months ago. We were in a long distance relationship and things were tough, but nothing that we couldn’t overcome. He told me he wasn’t happy anymore and that we needed to work on ourselves apart because it wasn’t working when we were together. My heart was broken. I was desperate. I cry whole time, until I found this website http://magical-rituals.com I used that. I was amazed when love spell start working. He start calling me, apologized and finally back to me. I never believed in that things, but now I do.