I can see how that could be extrapolated from the Genesis account of Cain and Able. If Cain went to the land of Nod and started a family, there had to be other people at least contemporary to Adam and Eve:Yes, that is one of two possible answers to the question of how Cain found a wife in the Land of Nod as I see it. I think it's cool that the pre-flood world had a land of Nod. 
The other answer is that Cain married someone from his extended family. We don't know how much time passed from the time Able and Cain were born to when Cain murdered Able. If could be hundreds of years for all we know. The Genesis account just doesn't give those records. If so there might have been a large population since the Lord told Adam and Eve to be fruitful and multiple.
Yes, that is one of two possible answers to the question of how Cain found a wife in the Land of Nod as I see it. I think it's cool that the pre-flood world had a land of Nod. laughing
The other answer is that Cain married someone from his extended family. We don't know how much time passed from the time Able and Cain were born to when Cain murdered Able. If could be hundreds of years for all we know. The Genesis account just doesn't give those records. If so there might have been a large population since the Lord told Adam and Eve to be fruitful and multiple.
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It is hard to make heads or tails about it. I noticed Cain said he was driven from the face of the earth. One meaning would be “disappeared”. I overlooked your bolded (Land of Nod) in my first reading
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Easton's Bible Dictionary gives the following definition of Nod, saying that it means "exile; wandering; unrest, a name given to the country to which Cain fled. It lay on the east of Eden." The Book of Genesis was written by Moses during Israel's 40-year wilderness exile.
Genesis
13 And Cain said unto the Lord, My punishment is greater than I can bear.
14 Behold, thou hast driven me out this day from the face of the earth; and from thy face shall I be hid; and I shall be a fugitive and a vagabond in the earth; and it shall come to pass, that every one that findeth me shall slay me.
15 And the Lord said unto him, Therefore whosoever slayeth Cain, vengeance shall be taken on him sevenfold. And the Lord set a mark upon Cain, lest any finding him should kill him.
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I believe that Nod is a place out of Gods sight, which is reasonable because God won’t look on sin. but I still can’t fathom where the people would come from that would possibly kill Cain or marry Cain…Your explanation sounds reasonable as any 😊