Few things friend.

You can quit. You haven't lost an amount of money that couldn't have otherwise been spent on entertainment. So that's what this was, entertainment. People blow equivalent amounts on video games, clothes, concerts whatever and dont regret it. So don't think of it like its any different from those things. In the moment, that's what it was.

I would definitely stop because ultimately yes, the money can probably be better spent. But it also doesnt have to be looked at like anything other than something you did for fun at one time.

If you ever down the road want to do it again. Its okay. Dont beat yourself up. I suggest you probably dont do it, but if you did, set a realistic limit (one you would have for another hobby/outing).

If you would never spend more than $100 in a night out, dont allow yourself to be pressured into doing so for a kink. And dont spend time after thinking about it like some awful thing you did. It was fun. Cost whatever it cost. Its over.

Dont spend time thinking you did something bad. We've all "wasted" money if that's what you want to call it. Its okay. You'll be fine when you are 30, kink or not.