I have nothing to add to what Claire said, but want to suggest that you try to avoid "get", "got", and "gotten". Your vocabulary will expand if you avoid these ubiquitous words. Sometimes they are unavoidable, but try. "I read (through) the two books quickly because they were easy" "I finished the two books" "I devoured the two books" (dramatic, say only if you really liked the books)

Either. A denser novel would take me longer - generally. A denser novel would have taken me longer - in the past, instead of the short novel you actually read. Both make perfect sense.