Hey man a couple things I thought this lacked. Where was your tripod? There's no excuse to not use one when your not moving. The shaky shots at the beginning turned me off to the piece.
There was a lot of nat sound/pop opportunities here I felt you missed. You had the music in there but you needed tight shots and lots of them. Drums, fingers playing on trumpets, director swinging his or her arms etc. You can match the edits with the music later, especially with a song that repeats itself like Stars and Stripes Forever.
Same goes for the fireworks. I saw the wides and the nat pop but where was the tight shots of kids watching, their faces lighting up when the firework explodes, etc. I want you to take me there. I really noticed the pans to nowhere. If you are going to pan keep pan short, not the time but the distance you cover and take it somewhere, make it serve a purpose.
And for my last "critique" once I see someone I don't need or want to see them again, especially in a piece like this. Unless its an emotional moments or adds to the story I don't need to see them again.
I'm not trying to be harsh here but I felt like this was a major missed opportunity. I don't know what kind of crunch you were under but your trying and that right there is half the battle. Develope a thick skin and keep working hard and watch a lot of other stuff posted here. There is a wealth of knowledge here so keep at it!
The one good thing you had in there was the interview - framed and good placement for light. The series of opening shots were way too generic...all wide or high and no detail. You need close-ups as photoguy pointed out. Those are what draw people into the story and make them feel as if they are part of it. The hop from daylight to evening was a bit disconcerting...and then back to a daylight interview. If you're going to do that cover up the interview with b-roll.
OK - now: how to get better. Get over your fear of getting close to people and standing near the performers. Unless you were stuck on top of your live truck for a series of live shots, move around in the crowd. Look for personal moments...people interacting and having fun (or not). For every wide shot take another medium shot and ten or more close-ups. Build sequences...a series of shots that tell a story. Wide shot of crowd...medium shot of little guy on dad's shoulders...close-up of little guy's face, close-up of little guys dirty little hands holding a snow-cone dripping icy water on dad's head, close-up of dad's reaction to water. Wide shot of band...medium shot of front row of audience...close-ups of feet tapping, people smiling, hands clapping. Don't just show us a scene...show the human reaction to the music and fireworks.
You've got a long long way to go...but I shudder when I think of my first stories that I was proud of. I still shudder.