Can you tell me is anisometropia really bad?

Anisometropia: Basically means that there is a significant difference in the glasses correction between your two eyes. In children, this could cause one of the eyes to become lazy. If this develops in adults, it's often due to cataract formation. Anisometropia is not damaging to your eyes but will cause problems with eyes working together if this is significant enough. Talk to your eye doctor about this.