@kad13 If you have symptoms that last more than about four seconds, and have time to take your pulse somehow and find that it is running over 100 BPM, the chances are that you have a tachyarrhythmia, possibly atrial fibrillation. That rate, over 100 BPM, might also mean you have what is called 'rapid ventricular response'. Some people fibrillate under 100 BPM, and that means their left ventricle is not trying to keep up with the left atrium when the atrium begins to fibrillate. Much above an indicated 100 BPM means your ventricles are trying to beat in concert with the rapidly beating atrium.

If this ever goes on longer than 24 hours, get to an emergency room and tell them what has happened.

PACs should NOT make you breathless, not the couplets, triplets, or quadruplets you say you are experiencing. Breathlessness tells me, an untrained non-medical person, that you have what is called 'supra-ventricular tachycardia', and it might be the atrial fibrillation variety. The only way to be sure is to have a 12 lead ECG done when it is happening, and it's not likely in view of the self-limiting nature of your arrhythmia.

What I suggest you do, if you have the means, is to acquire a Kardia Mobile 6L. You can get them from amazon over night. They're not expensive, and sometimes on sale, so shop around. You don't need their subscription service, but the device can show if you have atrial fibrillation or some other indeterminate arrhythmia (it won't diagnose anything that isn't atrial fibrillation as far as I know). You can show the readout to a physician who would then presumably become your advocate to a cardiologist or to an electrophysiologist.