No, the noun 'state' is a common noun; the noun 'creek' is a common noun. A 'state creek' is a compound common noun, a word for any creek within any state.
A proper noun is the name of a specific person, place, or thing, for example:
No, the noun 'state' is a common noun; the noun 'creek' is a common noun. A 'state creek' is a compound common noun, a word for any creek within any state.
A proper noun is the name of a specific person, place, or thing, for example: