Don't worry about it, I solved it.
I had a line in my code that was "parent": "item/handheld", that completely messed with the model, I removed it and everything is as it should be.

So I've made a custom item texture and model for Minecraft, I directly exported it from cubik studio, I have triple checked that everything is in the correct folders, and after looking through some other posts, I ran the JSON file through an online validator, however, my custom item is still ...