Why does some sour stuff make peoples tongues bleed?

The main ingredient used to make things sour is a substance called malic acid. While it's safe to eat, large quantities of it can cause minor damage to skin and flesh, especially sensitive or thin skin like that found on the tongue.

Some people are more sensitive to foods or ingredients in candies and things. You need to stay away from it, they call it toxic waste for a reason.

Allergies 🤷‍♂️

I’ve never experienced that

its likely burning your tongue with chemicals

Your tongue bleeds that seem unusual