Can growing pains last for days at a time?

My 5 year old son started saying his leg hurt (just one) about 2 days ago, and he has even had a hard time walking on it. My husbands sisters said they had REALLY bad growing pains, but when I looked it up it says that normally they are gone by morning. That's not the case it started at night a few nights ago, and he has been limping for a few days. I called the Dr already. We have an appt this afternoon but I was just trying to see if anyone else has gone through this before.