Heart flutters and frustration

hi, I've had all the tests as well. My episodes come randomly, but I feel like they mostly come around the time of my period. I get them less now thankfully. My heart rate will skyrocket 30-40 points for no reason. This can last 2 minutes to 20+ mins. I used to be able to feel palpitations, but now I no longer feel my heart beats. When it first started after the birth of my baby i would get a huge rush of lightheaded ness ( like the oxygen was cut off to my brain for 2 seconds) then my heart rate would jump up to 115 fun like 65bpm. I had one in December that went up to 140bpm. Really scared me that time. They used to be a few times a month now I get 1 a month or less. My very first episode was me having a cup of coffee, looking outside and a bright light shinned my eye the wrong way, and my eyes started starring over to the point where all I could see is blotches. I was right on the cusp of passing out, but thankfully I did not. I felt like I was going to die. It was very scary. And ever since the following summer after that, I've been having these rapid heart rate episodes. No one can figure it out, and I feel like maybe it is an autoimmune disease caused by having a baby, or endocrine disorder, I thought maybe it was from low iron just recently, but I had another episode last weekend and I've been taking iron for almost 2 months. I'm doing a DNA 100% gnome test to look for rare disease. It should be done in a few weeks.