How do I know if my toe is sprained or broken?

I stubbed my toe (toe beside my little toe) 3 weeks ago. At first it swelled & bruised, I haven't seen a doctor yet. Just the other day it bruised again, I haven't been able to wear any running shoes I have been wearing flip flops as that is the only thing comfortable still to wear. I have not been able to move the toe properly & still I get pain from my toe. So I was wondering is it broken or sprained?