I have never done self aid on myself, but with a chronically I'll daughter I have :
Recognized strider and went through the debate in my head if calling 911, I then chose to get her in the car and drive her to the hospital as I could get her there in 3 minutes or less. I also called ahead.
I have recognized wheezes, crackles , rales and a plural rub . Once while she coughed blood out. Again, I just loaded and went.
I looked at her and immediately knew what they meant by "circling the drain " and she was then sent by ALS to a larger hospital after being stabilized. She had gone into shock.