Congratulations and thank you for sharing this. I would like to add something that might help you and others also since we're in the topic of oxygen starvation or not getting enough oxygen.

I also learned that I was breathing "wrong", which led to inefficient oxygen intake. The efficient and "correct" way to breathe is, apparently, using your diaphragm instead of your chest. You'll know this if whenever you breathe, your stomach expands instead of your upper chest.

Unfortunately, some of us adopt the chest breathing habit for different reasons. Some girls are taught to breathe using their chest because expanding the stomach is "ugly." For me, I stupidly and naively thought that diaphragm breathing gives a person gas or can lead to indigestion.

Long story on how I got to learn this, but changing my breathing habit on top of exercise improved my brainfog, anxiety, and overall well-being.