On my iPad Pro, when I swipe left on the main screen it no longer goes to my other screens. I get a pop up of my apps bucketed in categories I didn’t create.

First, swiping past all of your Home Screens will take you to the App Library page - where you will find all of your installed Apps listed in automatically grouped folders - and alphabetically. You should note that your App Library is independent of any App folders - and arrangement of Apps - that you have on your Home Screens.

Organize your apps in folders on iPad - Apple Support

Automatic grouping of Apps within your App Library is determined by the category in which individual Apps are listed by the respective Developers within the Apple App Store. These groupings cannot be changed.

Find your apps in App Library on iPad - Apple Support

Returning to your issue... try a forced-restart of your iPad - as this will often clear an isolated software issue:

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.

If the problem persists after performing the restart, it may be necessary to reset your iPad settings. While this reset will not cause any loss of data, as a precaution, it is always wise to ensure that you have a current iCloud or iTunes backup before performing the reset:

How to back up your iPhone, iPad, and iPod touch - Apple Support

When you are happy to proceed, you can perform the reset from iPad settings:

Settings > General > Transfer or Reset iPad > Reset > Reset All Settings

If the problem still doesn’t clear, the next step is to reset the iPad to factory settings:

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

Otherwise, you would be best advised to seek assistance directly from Apple Support. You can contact the Support Team using the Support link at top-right or bottom-left of this page. Alternatively and perhaps easier, you can initiate and manage your support cases using the excellent Apple Support App. If not already installed on your iPad, the App can be downloaded from the App Store:

https://apps.apple.com/app/apple-support/id1130498044

You might also visit the Genius Bar at your local Apple Store or Apple Authorised Service Provider (AASP) - where the technicians will be able to assist:

Genius Bar Reservation and Apple Support Options - Apple

Sounds like all that happened was you were on your last Home Screen and swiped left again.