My wife has small ears and we share an earbud each on the plane everytime. We're very impressed with these headphones and they're only $25. I'd pay double at least. She hasn't tried running in them, but I don't think you'll have a problem
The blue light continuously flashes when turned on to signal that the device is still on. There is not proper way to disable it. Without the light or playing audio how else would you be able to tell if the device is on?