How we cite our quotes: (Page) Vintage Books, 1989
Quote #4
... And to clear my mind, I sucked in the wind and screamed. The sound went out, violent, to the rims of the world, and after a moment it bounced back up at me—harsh and ungodly against the sigh of the remembered harp—like a thousand tortured rat squeals crying: Lost! (45)
Grendel's just found out that he is the distant relative of the worst person who ever lived (or close to it)... and that humans are apparently awesome, despite what he knows to be true about them. So, yeah, he's not being too dramatic—it's a bad day when you find out you're on the dark side of history.
Quote #5
My heart was light with Hrothgar's goodness, and leaden with grief at my own bloodthirsty ways. I backed away, crablike, further into the darkness—like a crab retreating in pain when you strike two stones at the mouth of his under water den. (48)
The Shaper's version of events persuades even Grendel to think more poorly of himself than ever. He's been cast as the villain of the piece, and he really feels the psychological pain of his separation from the rest of creation.
Quote #6
I discovered that the dragon had put a charm on me: no weapon could cut me. I could walk up to the meadhall whenever I pleased, and they were powerless. My heart became darker because of that. Though I scorned them, sometimes hated them, there had been something between myself and men when we could fight. Now, invulnerable, I was as solitary as one live tree in a vast landscape of coal. (75-76)
It's bad enough that Grendel has to live outside of society because he's the cursed "kin of Cain"—now the dragon has gifted him with another degree of separation from humanity. This new invulnerability makes him even more monstrous and gives him another reason to use his power in wicked ways.