Unfortunately, Sandra, this is not an uncommon story. I wish I could say you're in 'good' company, but....you're not alone.
The palpitations, unless determined via a device that can read it properly to be AF, are likely to be PACs, or premature atrial contractions. The heart gets a double beat, and then skips a beat, and then compensates for the skipped beat with a thump. The thump is what is unsettling as it is what we feel, and it's outta whack...as you well know.

However, there can also be rather long, and worrying, pauses, sometimes lasting several seconds. Often this is due to the heart wanting to be in NSR (normal sinus rhythm), but beta blockers or calcium channel blockers are preventing it from keeping up. In my case, when my first ablation failed at a whole whopping six days, I was in the ER with pauses that ran....the nurse who came rushing in from the hall station held out her two index fingers about 6 inches apart, saying my heart had stopped beating for that long on their monitor. I went on amiodarone right away, but stopped my 50 mg of metoprolol cold. The metoprolol was interfering greatly with my already irritated heart's desire to restore normal rhythm.

Also, it's not unheard of for Flecainide, if you're on it during the blanking period, to actually make things worse. It brings on arrythmia in some people, and the EP will have to find a different medication, maybe Sotolol or propafenone. They didn't fool around with me and I went on the Big Drug right away...amiodarone.

I can empathize with how it makes you feel, and how exhausting and unrelenting it seems. I was there. Friends and family told me I looked grey.

Yet more information: it isn't uncommon for an apparently successful ablation to suddenly break into flutter. Happens surprising often, and it can also be relatively straightforward to nip with, unfortunately, yet another ablation. Again, happens all the time. In my case, and this is also common, you don't show AF on the Holter monitor at the 10-12 week assessment, but you'll show quite a few PACs. When the outreach nurse read my results to me over the phone, her voice emphasized '...a LOT of...' PACs, which at least told me I wasn't going crazy.

It sucks going several good days after an ablation only to find something else taking its place. On both ablations, I was fine for days, then had to go to the ER. They simply sent me home with more metoprolol the second time, and I eventually reverted to NSR. The same outreach nurse, when she learned they didn't want to cardiovert me, told me, again emphatically, that the decision was absolutely the WRONG one. Every time your heart is adjusted via surgery, it's a cranky beast, but it's also a 'reset' beast. You treat it like any other new arrythmia, and I should have been offered a cardioversion. But, I ended up being fine from the day I reverted to NSR, later that evening, and have not looked back since. I celebrated my year without arrythmia in February, and my heart continues to beat properly. So, there's hope for all of us. It just sux waiting and enduring.