heart palpitations

anyone else get really bad heart palpitations during third trimester? currently 36weeks 3 days and over the last hour they're happening as fast as they're going...also having a hard time breathing during the heart palpitations. has this happened to anyone else? i don't wanna go to the hospital if it's something normal during pregnancy...also had 2 cups of red raspberry leaf tea tonight, don't know if that could be causing it..can't find anything online