ok now that's 100% ducklips. When duck lips progress, they get that hump btwn their head and nose like that. Next stage, fungus will form around his head and become holes and it's a goner by then.
Keep treating him with metro and if it doesn't show improvements, double/triple dose it or dose the directed amount daily. (metro usually don't show any side effects when overdosed) BTW, what brand metro are you using?
wish he gets better,
JP