I've actually always had a problem with my hair curling after a cut, my son too. Especially if it was a lot, it does come back eventually least for me and my son. Anytime I do anything more then just a trim then my hair goes into what my family would call "shock", and go straight for awhile.

I've avoided big cuts like the plague since I was old enough to make my own hair choices since so I can't say how long it takes to grow back.