diff --git a/app/assets/javascripts/sitewide/form_errors.js b/app/assets/javascripts/sitewide/form_errors.js
index 8a11b5723..789ce42bc 100644
--- a/app/assets/javascripts/sitewide/form_errors.js
+++ b/app/assets/javascripts/sitewide/form_errors.js
@@ -42,8 +42,9 @@ var renderFormError = function(ev, input, errMsgs, clearErr, errAttributes) {
     }
 
     var $errSpan = "<span class='help-block'" +
-      errAttributes + '>' + errorText + '</span>';
+      errAttributes + '>' + errorText + '.' + '</span>';
     $(input).after($errSpan);
+    $(input).closest('.modal').modal('handleUpdate');
   }
 
   var $parent;
diff --git a/app/assets/stylesheets/shared/form_errors.scss b/app/assets/stylesheets/shared/form_errors.scss
index d0ec643f0..52a441c8a 100644
--- a/app/assets/stylesheets/shared/form_errors.scss
+++ b/app/assets/stylesheets/shared/form_errors.scss
@@ -4,3 +4,10 @@
     color: $brand-danger;
   }
 }
+
+.form-group.has-error {
+  margin-bottom: 0;
+  div.form-control {
+    height: auto;
+  }
+}
diff --git a/app/controllers/experiments_controller.rb b/app/controllers/experiments_controller.rb
index 13eb02177..795df0279 100644
--- a/app/controllers/experiments_controller.rb
+++ b/app/controllers/experiments_controller.rb
@@ -310,7 +310,7 @@ class ExperimentsController < ApplicationController
       view_type = view_state.state['my_modules']['view_type'] || 'canvas'
       path = view_mode_redirect_url(view_type)
     else
-      message = service.errors.values.join(', ')
+      message = "#{service.errors.values.join('. ')}."
       status = :unprocessable_entity
     end