The snippet provided doesn't give enough information to determine the overall structure of the story (problem and solution, chronological order, or cause and effect). However, the mention of an ice-cream headache doesn't inherently suggest a specific structure.
If the story goes on to describe the experience of having an ice-cream headache, how it occurred, and then perhaps offers a solution to alleviate the pain, it might follow a cause and effect or problem and solution structure.
If the story unfolds in a step-by-step manner, describing events in the order they occurred, it could be chronological. Without more context, it's challenging to pinpoint the exact structure.