Very worried :(

Hello everyone! I've been very worried about my chinchilla :( At Monday's night he fell from the stairs in 2nd floor right to 1st floor. We couldn't take him to vet that night because none of then work at night. I stayed up with him all night and I noticed that he was pretty calm and kept touching his nose with his paw. He sneezed quite a bit too. When morning came we took him to the vet right away. The vet said he looks fine, but he prolly hit his nose a little bit, that's why he keeps sneezing. She gave him an injection that would clear up his nose. He stopped sneezing and touching his nose, but he's still pretty calm and that's why I'm very worried :( Nothing else is wrong, really. He eats his food, treats, hay, he drinks, he bathes in his dust, he reacts to us. He walks and hops around just like he used to, just slowly. Vet said it's probably from the stress because like I said everything else is fine. I'm just very worried and I wanted to ask what do you think ? Should I be worried about him and take him to vet again, or does he just need to rest for few more days? :(