Another #MastodonTip for people of the #TwitterMigration (other than using camel case for hashtags) is that Mastodon instances are not run by corporations with thousands of employees. Usually it is just a handful of volunteers and an instance owner or two.
A huge influx of users, like this, all at once is a lot to handle. Stuff may break or slow down for a bit.
It'll be okay. Things will level out & it will all work again. The same thing happened in back in April.
Be calm. Carry on.