Sand here, sand there,
The sand is everywhere
Well, this part is probably not good. A big cliche is to say, "Here, there, and everywhere." I don't think it is going to be useful in the poem, because it s already all used up.
The imagery is great! I like the way you think, but this is not a self-analysis. This is a poem about the beach. ... but wait a minute, what do you mean about analysis? You are supposed to analye the poem?
Google this: poetry analysis
It will be easy to understand how to analye a oem if you look at a few web pages.
:-)
The ending is great.