Did I ruin my cartridge or my stylus? Or both?

Something happened to the cart, time for repair/replacement.

Possibly the stylus only.

I can't see how the innards could have been damaged.

I've on occasion managed to lower my cart onto the felt mat of my turntable without any obvious issues thereafter.

At the Radio Station where I used to volunteer, the cartridges were subjected to all kinds of abuse without breaking.

It usually took something catastrophic to result in the station having to fork out £30 for a replacement stylus (mid 90s prices).

Anyway, I was sad to read of your misfortune.

That really was unlucky, but before doing anything I'd give that sylus a really good clean first.

It could be that some vinyl/gunk became welded to the stylus.

Perhaps someone could chime in with the best way to safely deep clean the stylus?

You should invest in a 10x jewelers loupe. It enables you to see the stylus much better. I say 10x as it is still relatively bright. The higher magnifications limit the available light. I'd say that upon inspection, and no visible damage seen, I recommend cleaning the stylus with a wet clean stylus cleaner, such as the one made by audio technica.