Please use the Question Tags to state the name and full version number of the Story Format you have selected for your project, as answers can vary based on this information. I will assume that you are using the Harlowe v2.1.0 story format which is the default for the older Twine v2.2.1 application.
You can use the (set:) macro to create a Boolean story variable to track which path the Reader took through your story, then later use the (if:) macro and the current value of that story variable to determine what message to show the Reader.
1. Initialise the story variable being used to track if the clothes where changed or not within your project' startup tagged special passage.
(set: $clothesChanged to false)
2. In your "change what you wear" passage update the story variable to indicate that the clothes were changed.
(set: $clothesChanged to true)
3. In later passages use the current value of the story variable to determine if the clothes were changed.
(if: $clothesChanged)[hey you changed your dress]\
(else:)[hey why didnt you change your clothes]
note: If necessary you can use the Boolean data-type's not operator to determine if the story variable currently equals false.
(if: not $clothesChanged)[hey why didnt you change your clothes]