How do I know if I have thyroid heart? My heart seems to beat a bit faster than the norm but im slightly unsure, please give me major sign for sure.

Check thyroid labs. The best way to determine if someone has a thyroid problem is to talk with a doctor, get an exam, and check thyroid labs to see if their levels are right for them. While too much thyroid hormone could cause a fast heart rate, there are many other causes that a doctor can check out as well, including caffeine, smoking, poor conditioning, certain meds, heart problems, and anemia.