I'm 33 years old, and I've been through this twice in the last couple of years. Both times, I was unable to stand up due to the pain. The first time, I was so scared that I immediately tried to move my legs because I thought I was becoming paralyzed or something. It took around four days to heal; I had to stay in bed for the first couple of days, and it was awful. Since then, I've been incredibly cautious about the way I crouch or bend when picking up something.