It does look a bit out of alignment. It's possible that it was caught on something and got twisted up. It's not likely to pose a problem unless it becomes infected. Keep an eye out for signs of pain when putting pressure on it or reluctance to use that hand. Swelling or bleeding could also indicate a problem that warrants a closer look, but otherwise I'd just let it be. It might be a good idea to swap out the hammock or cover it with some fleece that won't be as likely to snare nails if it continues to be a problem.