i'm sorry to say but he is most likely done for but it sounds like his tracia is punctured or cracked ribs or a collapsed lung at all costs try to prevent infection with soap, boiled water, boiled wine or in the worst case even pee to steralize the wounds
do you feed them scraps if so may i suggest to not put them on the ground because he may have some sort of bacteria and also it may be internal bleeding i gave you the most comman cuses all may be a possability
i totally agree with you mine laid yesterday at 27 weeks old apparently they were supposed to lay at 18 weeks old. DO NOT LISTEN TO THE INTERNET LISTEN TO EXPIRIENCE