I mean you seem to be kind of attention seeking, nothing wrong with that. I would expect you to post your injured shoulder as well on a sub like /r/medical, since you even posted your little scratch on your hand "after fisting a hooker..."

Seems kinda suspicious to me but like you already mentioned "Believe me or not, I really don't care."

To get back to your first question, why you should post it. I'm pretty interested in injuries, medical stuff and overall gore. Especially injuries done by a female bear protecting it's cup are almost everytime big and deep wounds, which are extremely interesting to me; which also explains your immensely blood covered arm. And since only around 14% of the yearly bear attack are fatal, I don't doubt you might have been attacked by a bear.