Stage 4 Optional Challenge: How can I display different photos each time the user enters the same search term?

$(document).ready(function() {
 $('form').submit(function (evt) {
   evt.preventDefault();
   var $searchField = $("#search");
   // disable and change the text of submit button after clicking on it
   var $submitButton = $('#submit');
   $searchField.prop("disabled", true);
   $submitButton.prop("disabled", true).val("searching...");

    // the AJAX part
    var flickerAPI = "http://api.flickr.com/services/feeds/photos_public.gne?jsoncallback=?";
    var searchTerm = $('#search').val();
    var flickrOptions = {
      tags: searchTerm,
      format: "json"
    }; // end flickrOptions
    function displayPhotos(data) {
      // print a message if no photos are found
      if (data.items.length === 0) {
        alert("Sorry, no images match your search term '" + searchTerm + "'");
        //reenable the search field
        $searchField.prop("disabled", false);
        // reenable the submit button and change it's value back
        $submitButton.prop("disabled", false).val("Search");
      } else { // build the html while looping through the array
      var photoHTML = '<ul>';
      $.each(data.items, function(i, photo) {
        photoHTML += '<li class="grid-25 tablet-grid-50">';
        photoHTML += '<a href="' + photo.link + '" class="image">';
        photoHTML += '<img src="' + photo.media.m + '"></a></li>';
      }); // end each
      photoHTML += '</ul>';
      // add photoHTML to the webpage
      $('#photos').html(photoHTML);
      //reenable the search field
      $searchField.prop("disabled", false);
      // reenable the submit button and change it's value back
      $submitButton.prop("disabled", false).val("Search");
      } // end if/else
    } // end displayPhotos()
    $.getJSON(flickerAPI, flickrOptions, displayPhotos);

  }); // end submit

}); // end ready