I would first check here to see if your return has been efiled:
https://ttlc.intuit.com/replies/3319882
If you have already submitted your return: if it gets rejected then you can go in and make the necessary changes. If it is accepted, you will need to amend your return to add your W-2 information. The FAQ below will take you to a guide with the instructions on how to amend.
https://ttlc.intuit.com/replies/7276605
