looks like he/she got a major beating. no harm done by the looks of it. and i would say its hard to tell what sex they are until their fully mature.
heres mine i just took after feeding.its around 4'' now.
I will be adding some young stingrays to the tank (slowly, over a period of time), but they will be the only other fish in this tank. Once he heals up nicely, he may end up in the 220g I'm getting with some gar, a friedrichstalli, a festae, indo datnoid, and some pike cichlids. Or he may stay in this 90g. Not sure yet.