Is a fluctuating heart rate an emergency? or can it wait a month until the person can see a cardiologist?

You get the most from this site when you provide detailed information with your question. A persons heart rate will fluctuate naturally through the day depending on sleep/wake/activity/stress and other factors. Your post does not provide enough information to decide if this is a problem or not. You are welcome to start over with a new post.

Do you mean irregular heart rate, beat to beat variation or rate per minute changing from 80-150 depending upon your activity? At your age sinus arrhythmia is common which has increased rate during inspiration and decreased rate during expiration. Sinus arrhythmia is physiological and indicative of good cardiovascular health. See a doctor who can get an EKG and decide urgency. Hope it helps.