Please help don’t know if he is hurt

hi Guys I have an emergency question
My chin was hanging out on the edge of his cage while I had it open from the top. I always watch him when he does this because his cage opens from the top and not the side . The door is big so I have to hold it when he’s on the edge or else it would fall on him if it swings closed . He made a quick movement while I wasn’t holding it and it fell and hit his back I tried to stop it but it happened too fast . He didn’t make a weird noise or anything but I’m really worried that he has a bump or bruise idk if it’s my paranoia but it looks like he has a bump or bruise on his back. Kinda like a humpback. Again idk if it’s my paranoia and I’m noticing more things but his breathing looks a little harsh and he was sneezing after it happened. I feel horrible and don’t know what to do. I can’t afford to take him to the vet today but if I have to I’ll take him :cry3::cry3::cry3:

How is he now? Chins are pretty scrappy. I wouldn't think a door would do much damage unless it hit him just right. Hunchback is usually a sign of malnutrition, not injury. Is he moving around? Has he eaten, taken a drink, the usual chin stuff? The sneezing also seems to be a coincidence as one would rarely relate to the other.