My Apple Watch warranty is about to end. Am I able to get an extended warranty, if so, is it worth it?

It's too late. You needed to add AppleCare+ to your watch within 60 days of purchase.

AppleCare Products - Watch - Apple

M1 Mac mini, macOS 14.4;  Watch, series 7 GPS/cellular, watchOS 10.4; iPhone 12 Pro, iOS 17.4; TV 4th Gen, tvOS 17.4; HomePods, audioOS 17.4 and Airport Express w/ Airplay 2

How to buy

Purchase AppleCare+ with your new Apple Watch.

Or buy it within 60 days of your Apple Watch purchase:

On your paired iPhone (go to the Watch app > General > About and choose Add AppleCare+ Coverage)

Online (requires you to verify your serial number and run a remote diagnostic)

At an Apple Store (inspection of Apple Watch and proof of purchase are required)

By calling 800-275-2273 (requires you to run a remote diagnostic and provide proof of purchase)