No, your original refund will not be delayed due to you receiving a second w2.
After the IRS fully processes your return and you receive your refund, you can Amend your Tax Return by filing Form 1040-X to include your additional Form W2.
You can click here for instructions on Amending your tax return: How to Change a Tax Return You Already Filed.
The 2018 Form 1040-X is estimated to be
available February
14, 2019. You can
click here for information on IRS Forms Availability.
Note: You SHOULD NOT make any changes on your return in
TurboTax until this form becomes available.