When in the flashback, Yaz's hair goes between blowing in front of her face and being behind her ear.
It's never explained why Zellin strikes at Aleppo in 1380. There's no indication there that in all of time and space, the nightmares generated by the inhabitants are any stronger than any number of other hospitals and asylums throughout Earth's history.
It's revealed later in the episode that Zellin took Maryam prisoner and drained her nightmares. However, there's never any reason given for why. She appears to be a doctor at the Aleppo hospital rather than a patient. Regardless, there's never any indication that her nightmares are any stronger than anyone else's. Zellin takes Maryam instead of Tahira, when Tahira is presumably the mental patient with the strong nightmares Zellin needs.