+1 on asking your doc. (S)he has spent a significant portion of his or her adult life studying the human body and how it repairs itself. You're going to get a better opinion from him or her than you will from a buncha random folks over teh interwebz (no matter how nice the lot of these folks here are).
That being said, I'd be awful careful about using an hammock. I find that shoulder squeeze is the primary concern for me in an improper hang, and that'll put pressure right where you do not want it with a broken collarbone.