SQL & PL/SQL

Oracle Database 11g Enterprise Edition Release 11.2.0.3.0 - 64bit Production
PL/SQL Release 11.2.0.3.0 - Production
CORE 11.2.0.3.0 Production
TNS for Solaris: Version 11.2.0.3.0 - Production
NLSRTL Version 11.2.0.3.0 - Production


I asked a question here about some other code I was writing a little while back, and it was recommended that I try to incorporate a different style in my block.
So I'm trying to use the exists statement to check if a table exists. If it does, tell me. If it doesn't, create it.

BEGIN
   IF exists(select table_name from all_tables
                where table_name = 'WILLY_TEST')  
    then dbms_output.put_line('TABLE EXISTS');  
    else
CREATE TABLE FS_NRIS_FSVEG.WILLY_TEST  
(
  TEST_COL_1  VARCHAR2(1)                       NOT NULL,
  TEST_COL_2  VARCHAR2(1)                       NOT NULL
)
RESULT_CACHE (MODE DEFAULT)
STORAGE    (
            BUFFER_POOL      DEFAULT
            FLASH_CACHE      DEFAULT
            CELL_FLASH_CACHE DEFAULT
           )
LOGGING 
NOCOMPRESS 
NOCACHE
NOPARALLEL
NOMONITORING;

ALTER TABLE FS_NRIS_FSVEG.WILLY_TEST ADD (
  CONSTRAINT WILLY_TESTS_PK
  PRIMARY KEY
  (TEST_COL_1)
  ENABLE VALIDATE);
end if;
EXCEPTION WHEN OTHERS THEN dbms_output.put_line('Create table failed');
END;
/

I've tried it both as above, as well as with the EXECUTE IMMEDIATE and the block in Q ticks. (Q'{.....}';
I can get it to complete successfully, but it's a lie, because nothing happens. It doesn't create the table, nor does it error and tell me.

What am I missing or doing wrong? From what I've read, I have the exists function correct, the iif statement correct...I don't get it.

Thanks for your help.