It is always possible that something started makes something unforeseen happen. However, there is also a problem with what is called the 'post hoc, ergo propter hoc' fallacy, meaning something happened after I took this, so it must be because I took this. I ate an apple and then my dad died. Silly, yes, but it does illustrate the fallacy well. Your ferritin is low, so the initial first, and medically sensible, step was to start you on a weak dose of a drug normally well tolerated. It's safe, widely prescribed. It may still be what set your heart off, so I'm not dismissing the possibility, but on the basis of probability, this was most likely going to happen about now anyway. If you're getting on in years, the chances are your heart will start acting up, whether from ischemia/blockages or due to electrical disorder. Happened to me, and there are literally millions of us with electrically disordered hearts.
You need to see a cardiologist about this, so maybe get referred by your GP. He/she should be sympathetic and also want to ensure this isn't just a one-off. The fact that you have been plagued by arrhythmia for days now suggests to me that this is a new reality for you, and that it is almost certain not to be due to the supplement. I believe your GP will probably agree. In fact, and not to put too fine a point on ....umm....my point....sorry...please see this:
https://www.cardiovasculardiseasehub.com/archives/21680
It turns out that iron deficiency is most likely the culprit, and that you developed the arrythmia at the same time that your heart threw in the towel and that your GP put you on the low dose supplement. So, coincidental. Happenstance.
@gloaming
I started having these darn heart skips in my late 30's after mom had her first heart attack. I wore a 24 hour holter monitor and I only had a few ectopic beats, nothing else. Well, I had them off and on and some PSVTs (Paroxysmal Supraventricular Tachycardia)as well, but nothing major, but they scared me. I was fortunate that I never had a lot back then. After mom died from complications from vascular surgery, they started again and this time a lot more and more atrial runs. I wore 7 day events monitors , and had a couple of echocardiograms
This was when I was 49 to 54. Daddy died from cancer, and then the skips got worse again. I married a man from New Zealand and I moved there when
I was 55(I live here now)and the ectopic heart beats and PSVTs have taken a turn for the worse. I am now 68 and I live every day in constant fear of them. Every little strange best sends me into panic and I cry. I have worn two 7 day monitors once a few years ago and one a couple of months ago. I had an echocardiogram a year ago. All "normal" results. I have lost track of all the times I have gone to the ER, again, I am always discharged because all blood work and EKGs are normal. I just now had a short run of PSVTs, at least I think it was that, I am petrified of having A fib. I am sick with fear, no matter how hard I try, I can't stop being frightened. I am going to see my GP tomorrow to see if she'll refer me to have another echo done. I wasn't happy with the first as it said on one part that the image quality was only fair and poor subcoastal windows. I paid a lot for the exam, I want it done right. I should have said something earlier, but I didn't think about it. Lately, I have been having the ectopic heart beats all day and night which are horrible, they are not sustained but persistent all day. I don't know how much more I can take. That's when I really studied the echo report a few days ago and it concerns me, I am surprised that I haven't been called for another actually due to the fact of what it said about the images. Also, the cardiologist said it was "an essentially normal echocardiogram" It did show MAC-Mitral Annular calculation, but no stenosis and just very trivial MR. The aortic valve had some thickening valves, but no stenosis or AR. The rest of the report was OK. I am concerned that he didn't mention another review as it's been a year. I am so scared I can't think straight. I didn't think much about it when I got the report, but now that AI answers questions, I feel like I know more and I am doubting my doctors. I just can't stop being scared. Oh, ejection fraction good, it was 72.
I also have fibromyalgia, a hiatal hernia and costochondritis, I get sternal chest pain at times and that scares me. Again, all blood work and EKGs and time on the monitor while in the ER are "normal".
I have to have relief from these ectopic heart beat fears. I am feeling weird again in my tummy and chest, this usually precedes the skipped beats, I am scared. The doctor told me to take Ativan,but I am scared of it, I am 68 and have glaucoma and those are two things that the warnings on the drug say to watch for and to not take it. She said to cut it in 4ths, but I am still scared. I know lots of people that have these horrible heart beats take Xanax, but I don't feel safe in doing so. Beta blockers really aren't an option as my blood pressure is low normal and heart rate in the 60s to 70s even during the skips, it is elevated when I have PSVTs.
I also get them after I eat or drink water. I probably don't drink enough water due to fear of the skips starting when I do. Bending over and lying down can also be a catylist. I am a mess.😭