I'd totally agree with you that this is pretty cool! Not even I can get that close to a hawk on the ground unless I sit super still for like....10 minutes! You didn't even have to wait that long because the hawk was already there when you walked by it. I believe this hawk you filmed was a juvenile Red Tailed Hawk.

This is actually a Yellow Warbler, although it does look a little like an American Goldfinch. Thanks for sharing!