Try doing a search on your country here to find an avian vet https://www.aav.org/search/custom.asp?id=1803 without being seen by a vet it is not possible to say what the problem is but I would keep him warm and comfortable with food and water within his reach. How did he happen to fall are his wings clipped, did he break his leg or foot? Sometimes budgies will pant if they are stressed and that may be the case with your bird.

 

Unfortunately I do not know where exactly he is hurt - from the outside he looks fine
Oh thank you, I found another vet trhough this site!

 

What is the status on your bird? Have you managed to locate a veterinarian that can help you?

 

Good News: My bird did not move from the place where I put him over the night and still lied on his belly. However I now got him to sit on a perch and he is grooming himself! He also accepts water to drink. However it seems that my bird wants to rest and does not want to fly with the other budgies.

Thanks to Cody I found a vet and I will take my bird to him to be sure

 

Your budgie should remain quiet and resting until it is seen by the Avian Vet. He should be separated from the other budgies in the meantime.

 

Hi there and welcome to the forums!

You've been given great advice above by Cody and FaeryBee! I'm glad you're able to take your budgie into the vet and I hope it goes well.

Meanwhile, you've come to a great place to learn even more about the best of budgie care practices! Be sure to read through the forums' many budgie articles and "stickies" stuck to the top of each subforum to ensure you're up to date on everything! If you have any questions after doing so, please be sure to ask as we'd love to help.

Hope to stay posted on how things go! Best wishes 👋