Minecraft – How to get a new villager

The use of spawn eggs ignores most of the checks for whether something should be able to spawn somewhere. In particular, no check is made for amount of mobs already spawned. You can use spawn eggs to create hundreds, thousands, or even millions of mobs in an area; the only limit will be the processing power and memory needed to handle them.

This is a dupe question, but in short, unless you have made a backup copy of your world to a USB stick or the cloud service, your world is gone.

This appears to be a common (but seemingly random) problem after many of the Minecraft updates. The only cases where I've read of people recovering their world is if they had a back up and they roll-back the update. Restore the backup and try the update again.

Sorry for the bad news.