it is okay for your breast to hurt even without a bra on

Breast pain is normal, bra или no bra. it has to do with hormonal changes in your cycle, или just growing pains.

well, there should be a reason for it. Nothing hurts for no reason

That's normal. I am the same way.

As all the others have сказал(-а) to some degree its perfectly normal but if it seems to start to do it еще than it has или when Ты are not expecting it I would talk to someone so for now keep a note of dates when it does it and which side and see if there's any pattern to it. Then if Ты are further concerned go and talk to someone start by talking to your mum или at least a nurse.