Sounds like a PVC. The long pause and then the hard thump/beat is what a lot of us experience. I'm not sure what the 'clicking' could be as it seems that you hear it without a stethoscope? (a MVP will produce a click, but don't remember anybody hearing it without an aid).
I had the 'swaying' back and forth so bad that if I stood and closed my eyes, my body would do an involuntary circle and I'd fall over. Thankfully I was referred to a neurologically trained chiropractor (very few of them) who through 3 manipulations, some vibration therapy on the hands and finger jerking (sounds silly, but it worked), stopped the problem, including lowering my BP, HR and frequency of Palps. He explained the neurological reasons which are very interesting and logical. Your allopathic neurologists and doctors pooh-pooh this, but the treatment saved me. It's been ten years since my treatments (I can still close my eyes without falling over) and I'm considering going back just to see if it will stablize the heart rhythm.
If you haven't had an evaluation or worn a holter monitor, I would recommend seeing a cardiologist and make sure that all is ok. Peace of mind helps. Take care.
Taking a deep breath often makes my heart pause or seem to slow down immediately. Your heart doesn't need to pump as fast when there is an excess of oxygen in your lungs. A deep breath may make your heart slow for a few seconds. I'm no doctor, but I have experienced this almost every day.
I think that is a normal reaction to your breathing. Sinus arrhythmia they call it. However I'll let someone respond that acutally knows more than me.
Frenchie