I entered my name as Steve instead of my legal name o Stephen.. is this OK or do I need to redo?

If you have already filed, there is no need to redo your return.

Entering Steve instead of Stephen will not cause your return to reject.  The IRS matches the last four letters of your last name with your social security number for verification.

If you haven't filed yet, I recommend that you log back into your return, click "Take me to my return", and then click "My Info" from the left side of your screen.  From here, click "Edit" next to your name and change your first name to Stephen.  Although using Steve instead of Stephen shouldn't cause any problems, it is best to use your name exactly as it appears on your Social Security Card.