one day isnt enough to list.
i think the hardest part of shadowing is finding someone who will let you shadow. you've already done this, why not shadow more? it really is a good experience and ought to give you something to talk about in apps/ interviews. i spent somewhere around 30-40 hours shadowing for the past month and i plan to do more. not to pad my application but because i've enjoyed it a lot, and the more i see, the more i want to see!
especially with an ED doc- spending a few weeks would be great because who knows what you'll see? it's something different every day (hopefully.) this sounds like a good opportunity, take it!
edited to add:
i guess when you say you were visiting a friend . . . was really far away and thats why you can't keep doing it?