Well, "endings" is in quotes. Not literally. Ending as in the the "shootouts". The movie felt like it was about to end. And then it went on again with another shoot out. There are critics who say it's too long and I think editing wise there could be a way this could flow way better.
if you speaking on the shootout after the handshake scene. the only reason you may feel that way is because hilde was about purchased from her freedom and u was expecting some shootout in where django comes out successful in escaping.
but you missed the whole point of why the final act was necessary if you thought that way.
things do not come full circle UNTIL he was sold back to physical bondage, but this time with a complete different state of mind.