Cervantes used everyday popular speech in his writings back in the 1500's and this was acclaimed by his readers. He wanted to give an account of real life in Spain in his famous work Don Quijote and it is believed he conceived of the story while in jail. He was bankrupted several times and was jailed as a consequence,
Yes they are both forms of a noun.
Hear are other examples of nouns:
Sydney, boy, Paris, city and desk.
If you have it, it is a noun
