New person looking for observations & opinions

Hi, I'm new here and this is my first post! I was wondering what people thought of this thing I wrote a couple of months back, having joined this morning. I haven't been able to get any feedback from my music teacher at school (I'm in year 8, or, in the US, 7th grade) and want to know how I can improve it. Although I've had lessons in flute, recorder and, currently, bassoon, I don't have any training in composition, and think that the constructive criticism here would help me improve as a composer drastically.

It's based on looking back at the past with joy and sadness, and the bittersweet feeling that causes. The louder bit is supposed to be a rush of memories and the emotions they bring.

Thanks!  

Pleasant, generally speaking. It's nice in the first section how your augmented 4th is never in clashing range with the melody.
I found your string parts very cluttered. I understand how this could be the point with "memories flooding back" and whatnot, but I tell students not everything has to be so programmatic. The Romantic period employed a lot of representational techniques that work quite well.
The only reason I say it's cluttered is because there's a lot of crossed voices and unflattering non-harmonic tones and all the voices seem to be doing their own thing. This should feel fluid, right? Like a stream? Think about using a more gradual texture changing process like monophony -> homophony -> polyphony (but in the correct ranges; fugues and canons are hard!). It needn't sound so frantic already.
Your piano writing over time should change. Not necessarily the idea, since I get that that should be a constant presence. But there's no need for it to be playing the same registers and the same unmoving line over and over. It has its capabilities too!
Cheers!

Thanks! It's really useful to have an unbiased and experienced viewpoint - exactly what I needed!

put up a score if you can