How come I'm very ticklish? Is it good or bad to be ticklish? (10 points if you answer details)?

for good or bad as in instictive. I will often laugh before I get tickled. And when I'm tickled I completly loose it and often hit/run away lol! I also have big reflexes like whenever someone gets too close (espeically in haircuts) i kinda twitch to run away. Also in swimming I can never be the 'victim' because i punch/kick the person and get away (i can't help it :P)