What are the simptons of atrial fibrilation/flutter? what s the diiference between atrial fibrilation/flutter and sinus tachycardia?

See below: https://www.umcvc.org/conditions-treatments/atrial-arrhythmia#:~:text=Atrial%20arrhythmia%2C%20also%20called%20supraventricular,more%20than%204%20million%20Americans. Visit this site for information on this topic. Wish you good health!

REGULARITY: In addition to Dr Singh's good advice, the major difference between atrial fibrillation (known as A-fib) and either flutter or sinus tachycardia is that A-fib is irregular while flutter may be either, and sinus tachycardia suggests that the rhythm is of ventricular origin--simply faster than "sinus rhtyhm." Any flutter suggests serious heart disease and must be converted ASAP. A-fib may be asymp