fixed another stoopid error

threadr/login/index.php

@@ -22,10 +22,10 @@
         <p>
         <?php
           if (isset($_GET['error'])){
-            if (error == "credentials"){
+            if ($_GET['error'] == "credentials"){
               echo "Invalid credentials. Try again:";
             }
-            if (error == "session"){
+            if ($_GET['error'] == "session"){
               echo "Your session was closed. We are sorry for the inconvenience.";
             }
           } else {