I don't understand why you conflate these stories. These are three different events, though some scholars try to make them out as one. But the geographical details and other elements (anointing head or feet?) argue against that: Occam's razor points to three acts of anointing.

As for a possible prostitute, that is a much later interpolation by Pope Gregory I.

Concerning the inerrancy of Scripture, it is a claim the Scriptures do not make for themselves. II Tim. 3:16-17 is as close as it gets: "All scripture is inspired by God and is useful for teaching, for reproof, for correction, and for training in righteousness, so that the person of God may be proficient, equipped for every good work."

"Inspired by God" (literally "God-breathed") does not guarantee perfection... it is also a human word.