Pain in leg moved to abdomen to chest then weird episode with muscles

I recently had something weird occur, and when it was going on it scared the crap out of me. I'm not really sure in which group this really needs to be posted in so feel free to move it if it's in the wrong group or needs to be in several different groups, etc.?

Last week I was standing up and all the sudden had a very severe pain in one of my legs. The pain traveled up my leg to my abdomen which caused severe doubling over pain in my stomach The pain then proceeded from my abdomen into my chest resulting in chest pain.

Once the chest pain began it was like someone had taken a vacuum, and, literally, sucked out every drop of energy I had in every muscle in my body all at once. If I hadn't grabbed onto the nearby table I would have fallen because my legs had no strength in them to hold me up, at that time. Once the chest pain stopped I could feel all the energy returning to my muscles again.

From start to finish all this lasted a very short period of time-approximately 20-30 seconds. It was both very scary, and very bizaare.

Since that day, I've had several episodes of some pretty severe stomach pain that seems to band all the way around my stomach and back like a tight belt of pain. I've not had this pain before, but it is very similar to the doubling over type pain I had that day, but without any of the other symptoms that I experienced that 1st day.

When I reported all of this to my doctor he said he has no idea what caused it, but if it happens again he will order some testing to see if he can figure it out. His plan is to order a CT of the abdomen if the stomach issues continue).

My 1st guess on what might have happened was that perhaps I had originally thrown a small blood clot from my leg that traveled to, and passed through my heart?

My guess on the muscle issues is that when whatever it was was happening in my heart to cause the pain that perhaps all the blood had shunted away from my extremities and other less vital areas of my body in order to protect my heart at the time?

The only other strange issues I've had is that after getting my 2nd Moderna vaccine, which just could be a coincidence) but my labs have also gone somewhat haywire. I've had hypothyroidism for over 20 years, but now my labs are showing hyperthyroidism. I also am showing elevations in my platelets-(which also is why i suspected it could have been a possible clot), and elevations in both my white blood cells, and my monocytes.

Have any of you experienced anything like this? Do any of you have any thoughts on what this might be, or what could be causing it? Any input is appreciated. Thank you, and I'm sorry this ended up being so long.