@DeChant: Nope! The way DNA works is that we have pairs of each chromosome, while sex cells (sperm and eggs) only have one of each, which combine into the full set when impregnation happens. The exception is X and Y chromosomes: Women have a pair of X's (XX) while men have XY. When sperm are made, the man's XY splits into sperm with either X or Y in it, while a woman's XX just splits into X and X. That basically means that a man's Y chromosome is a copy of his father's, which is a copy of his grandfather's, etc etc. Men can have genes coming from any of their great great great grandparents, but we know exactly which one the Y must have come from. Mutations can also occur which change chromosomes slightly, so the Y chromosome is not a perfect copy throughout the family line.
Generally, this duplication means that if you have a problem with one of your chromosomes (like the 4th or 17th or whatever), its twin will act as a backup, unless it also has the same problem. In that case, having two identical copies of the same chromosome is actually a bad thing, because it means you can't correct any flaws on that chromosome, and that means birth defects.
So, just like how a sperm could have either an X or a Y, they could also have either your first or second copy of each chromosome. Which basically means there are A LOT of ways to make a unique sperm out of a person's DNA, and same for eggs too. The only way that self-impregnation results in a clone is if the egg and the sperm have none of the chromosomes in common, because every other combination results in at least one of the original chromosomes being lost and its twin being duplicated. And like I said before, two identical chromosomes is a bad thing, because it leads to birth defects.
It's like buying two copies of a jigsaw puzzle, mixing them together, splitting them randomly into two equally sized piles, and then trying to complete the puzzle, twice. That's not to say that self-impregnation is impossible (genetically), but just that it'd be exceedingly unlikely to create an actual clone rather than just a normal child. Hell, the child could even have a different eye color than the parent, among other things.
But ultimately, it is a work of fiction starring futas with huge cocks, so the daughter could be a clone, and it wouldn't even be the most unlikely part of the story. Feel free to interpret it in whatever way is more hot to you.