i did have a similar thing, not to the point it made me cry , but it eas a sharp pain on the under arm side of my left boob.
When i went for my seven day post op check i mentioned it to the nurse as it hadnt gone away,
She asured me that it was quite normal and was probably a nerve, she said your boobs and muscles have had quite a bit of tauma and to expect this sort of thing for the next few weeks or so,
you will find it will ease , mine did then i was fine then the all over stiffness came back for a few days , then that was fine then i had a pain in the centre of my chest, i feel okay at the moment just over 3 weeks post op, It gets better slowly .everything has to settle back down and knit back into place , just take it easy xxx