Simple and bittersweet. I wrote a poem about something like this once. I think it's something everyone goes through. Your description of Yesterday as fleeting is perfect. That is certainly how the past always looks in light of the present.

aw, that's sad :( Well written tho, you successfully portrayed your emotions through the poetry. Good job!

Oh, yesterday... I felt depressed before I read this, and this poem (no offense) only made me feel more depressed. Your poems always perfectly convey whatever emotion you want emphasized. They're amazing. You're amazing. Keep writing.

All my friends left for college and I don't see them anymore and this was really refreshing to read, good work.

Wolf.