SQL & PL/SQL

Hi guys,
I have a problem in my procedure. There are 3 parameters that I am passing into the procedure. I am matching these parameters to those in the table to delete one record at a time.
For example if I would like to delete the record with the values ('900682',3,'29-JUL-2008') as parameters, it deletes the record from the table but then again when I execute it with the same parameters it should show me an error message but it again says 'Deleted the Transcript Request.....' Can you please help me with this?

PROCEDURE p_delete_szptpsr_1 (p_shttran_id IN saturn.shttran.shttran_id%TYPE,
p_shttran_seq_no IN saturn.shttran.shttran_seq_no%TYPE,
p_shttran_request_date IN saturn.shttran.shttran_request_date%TYPE) IS

BEGIN

DELETE FROM saturn.shttran
WHERE shttran.shttran_id = p_shttran_id
and shttran.shttran_seq_no = p_shttran_seq_no
and trunc(shttran_request_date) = trunc(p_shttran_request_date);
DBMS_OUTPUT.PUT_LINE('Deleted the Transcript Request Seq No (' || p_shttran_seq_no || ') of the Student (' || p_shttran_id ||') for the requested date of (' || p_shttran_request_date ||')');
COMMIT;

EXCEPTION WHEN NO_DATA_FOUND THEN
DBMS_OUTPUT.PUT_LINE('Error: The supplied Notre Dame Student ID = (' || p_shttran_id ||
'), Transcript Request No = (' || p_shttran_seq_no || '), Request Date = (' || p_shttran_request_date || ') was not found.');

END p_delete_szptpsr_1;


Should I have a SELECT statement to use NO_DATA_FOUND ???