What should I do about this blood blister?

Leave it alone. The cells lining your mouth and tongue are replaced twice as fast as most of those in the rest of your body – it’ll be gone soon.

@syz Can I eat anything though? I’m scared to eat anything.

Sure you can.

You need to leave it alone. it will go away on its own.

Opening it up will make it worse, and it will take longer to clear up.

You might want to avoid spicy, or high acid foods like citrus and vinegar. They might irritate it a bit. Does it hurt at all?

@Judi No, it doesn’t hurt. But it’s just worrying me.

If it’s not gone or almost gone in a week, or if it gets worse instead of better, I would get it checked out, but it should start healing and I would guess be almost gone by Monday. You’re young. Your cells regenerate fast. :-)

They just look scary. The skin should form a safe cover. You can eat and use your lip normally unless you paly a wind instrument, which might bother it.

What they all said.

Blood blisters are Mostly Harmless. If you can manage to keep from shutting your lip in cupboard doors for a few days, it ought to go away. :D
Blood blisters on regular skin you might want to cover with a bandage, to help keep direct pressure off.

Go to a foot doctor.