"I still don't understand these PVCs at all "
The simple facts are not hard to describe. Here they are:
The 'Pacemaker' in the upper right atrium normally sets the heart rate, but it's important to note that every cardiac cell in the heart is intrinsicially rhythmic and contractile. They can are capable of contracting whenever they want, but happily, they generally sort of agree to abide by the timing of the pacemaker. Still, every now and then, there's a rebel or a cluster of rebels somewhere. If you have been diagnosed with PVCs, your rebels are in one of your ventricles.
When you have a PVC, the rebels cause the ventricle to contract earlier than usual. Because of the way the heart fills, this means the ventricle has not had the opportunity to get as full as usual, and as a result, this particular contraction is tiny, so tiny that people don't usually feel it at all.
However, the normal timing rules apply for the next scheduled beat in a normal heart: It cannot contract until certain electrical things happen (called repolarization), so there's a delay. That's the pause you feel. Since the chambers of the heart are elastic, this delay gives the ventricle a chance to fill a bit fuller than normal. Now, the 'Law of the heart' is that it is obliged to try to pump out all the blood that enters it with each cycle, and to do that, the slightly fuller ventricle has to give a big push on this contraction. THAT is the big thump you (we) feel.
Interestingly, everyone gets PVCs. Also interestingly, not everyone feels them, even the BIG ones. Those of us who have a more sensitive car alarm, so to speak, really pick up on them, though.
It's important to know that in otherwise healthy people, under 10,000 PVCs per day are considered insignificant by doctors. The awareness of these beats is annoying and worrisome, of course, but the heart is so adaptable and flexible that it (and the circulatory system) compensate beautifully and seamlessly for the odd timing.
The problem is really only the fear that more sensitive patients feel. Education and therapy can help a lot with that.
I see you're in New Hampshire. UMass hospital in Worcester, MA had an excellent electrophysiology department. I'd highly recommend Dr. Lawrece Rosenthal, who did mine.
If you are only have 100s a day odds are you may not qualify to be seen by an electrophysiologist. The most they would do would be prescribe beta blockers because intervening with an ablation holds more risk of creating more issues for you than leaving well enough alone. It's frustrating for the patient that is for sure because I had both svt and premature beats and the premature beats are definitely more disruptive than my svt with a heart beat racing in the 200s ever did. Besides working on my stress I have found that avoiding caffeine, sugary foods, carbohydrates, large meals and anything that upsets the stomach seems to help calm them down. If you work out try and do a proper warm up and cool down and drink lots of water. My premature beats went crazy after I had my ablation to correct my svt but when I went to see my EP they basically told me to not waste my money coming back to them because they really don't do anything to treat premature beats unless you are having upwards of 20,000 a day. Frustrating for sure but just try to pinpoint and work on your biggest triggers. In general all the literature says they are harmless in an otherwise healthy heart. Take care and hope you are able to get on top of them.