Malbim: Initially he did not plan to go to Nayos. He thought that Shmuel will return to his house in Ramah. Also, it is not honorable to request David in the place of the Navi. He wanted to go to Ramah, thinking that the Navi will come to greet him. When he came to the great pit, on the crossroads between Nayos and Ramah, he retracted, and asked, where are Shmuel and David - in Nayos or Ramah?

Radak: Secho is the name of a place. Even though it is atypical for a place to have Yedi'ah [a Patach under the Beis, which is like the prefix Hei], we find like this - "ba'Karkor" (Shoftim 8:11), "ba'Sukos ¹ ".