After a wisdom tooth is removed, definitely there will be a hole created, but it instantly gets filled up with a blood clot and eventually it heals up in a few days.
If it is not paining, it will heal up in 3-4 weeks. Nothing to worry.
Health Tips
Precautions to be taken are: not to chew hard food from the treated side and after every meal rinse thoroughly with water/mouthwash to avoid entrapment of any food particle.