Wow, can you post that in English?
What you want to do is create a non-editable text box with the status of the repsonse that the user can't see (set to Visible = No). When your message box pops up, add either correct or incorrect, or some value, to the hidden text box. Use ONE text box for both a correct and incorrect response, bound to a single field in your exam table (junction table).
Then create a query to do the calculations for you. For example, if you use Correct and Incorrect, create a query that counts the instances of correct and incorrect for the user and the test. You can use this to display a running total score on the exam form using the query and a subform.
Did that help? Did you learn to write on a cell phone? =)