That could even be individual preferences. I don't think anyone in my family used the term "creepy crawly" when I was growing up. It was either bugs, or the bug name. Usually,the bug name. Moths, spiders, potato bugs, roaches (that we did abbreviate from the longer form), sow bugs, centipedes, butterflies, etc. If memory serves, the reason we were specific in what we called them was because my father identified them. He was a scientist (not in bugs or biology), so he was more specific. One time, when he was visiting Texas, he saw a roach there and had to ask, "Do you shoot it or spray it?"
As an adult, I did refer to a guy who gave me the creepy crawlies"--at the time, my best friend was jumping out of a relationship that was going nowhere and decided to get married to this guy a week later to get it over. Even the other men (we're talking soldiers) all described this guy in the same way I did. She divorced him two weeks later.