Thomas worries that the Changing will make Alby psychotic like Ben, especially since he was so late in getting the Serum.
As he continues to recover from his ordeal, Thomas is plagued by a feeling of hopelessness. Being unable to avoid hearing Alby's screams of agony isn't helping his spirits much either.
Chuck brings Thomas some dinner and informs him that he's the talk of the town for coming up with a way to kill the Grievers.
Newt visits them too and says that the worst of the Changing is over and Alby should be fine. Then, reluctantly, he explains what the Changing is like: when you get the Serum your body seizes and your skin bubbles and turns a creepy green color while you are violently ill. Sounds awesome. But it also temporarily allows you to have your memories back, at least some of them. No one who's been through it ever talks about the Changing, but afterwards they are almost always unlikeable and moody (like Gally).
Newt also informs them that there isn't much change with The Girl either, and once again Thomas is left wondering what their connection could be.
Then Newt drops the bomb that there is going to be a Gathering the next morning solely to discuss what they're going to do with Thomas.