Well this is certainly a strange Angel Trumpet bloom.  The outer skirt of the bloom is a deep green while the inner layers have colored up. it is not uncommon to find the innermost skirt to be late to develop, but I have never seen this happen with the outer skirt.  It is almost as if the skirt layers are reversed in this bloom.  Perhaps it was just the first bloom jitters for this brugmansia seedling?  I'm anxious to see what the next bloom does.