I just made the stupidest mistake ever

I know. I know. I know. I know.
I know i'm not supposed to be so selfish.
I know i'm not supposed to feel this way.
I know i'm not supposed to treat everything as if it was last year.
I know things and circumstances have changed.
I know everybody around me changes, some for the better, others for the worse.
I know some people find changes in me as well.
I know i'm supposed to be a little more mature than this.
I know if i lose grip i'd end up like this.

I'm sorry for feeling so selfish, i know its selfish thats why i don't mention what. But i can't help but feel this way. This, is beyond comprehension. I can't even understand myself