I'm a 25-year-old woman with a BMI of 22.5, and I've been having episodes of tachycardia from time to time. My resting heart rate is usually in the 90s to low 100s, and I don't have any personal or family history of heart disease or drug use. The most recent episode happened yesterday, and I finally got an EKG. It showed sinus tachycardia with a short PR of 100. I work in an outpatient clinic, and a coworker did the EKG for me. Should I be worried about this?