Yes, the earnings need to be included as income on your 2017 tax return. You'll do that in 2017 TurboTax by entering the code PJ Form 1099-R and in the follow-up indicating that it's a 2018 Form 1099-R. You are also subject to a 10% early-distribution penalty on the earnings if you were under age 59½ at the time of the distribution. If you were older than 59½ you'll need to claim on line 2 of Form 5329 an Other reason exception to the early-distribution penalty.
Your question suggests that your modified AGI was in the phase-out range for a Roth IRA contribution, so the addition of the earnings to your AGI will cause more of your Roth IRA contribution to be excess unless you had returned to you more of the Roth IRA contribution than TurboTax originally indicated was in excess, so you'll still have some amount of 6% excess contribution penalty for 2017. If that's true, it's too late to correct this remaining excess for 2018, so you'll also have a 6% penalty on this amount for 2018 unless you can apply the excess as a 2018 Roth IRA contribution. (If you have already made the maximum permissible amount of new Roth IRA contributions for 2018, you can obtain a return of contribution for enough of the new contributions to make room to treat the excess as part of your 2018 contributions, keeping in mind that any earnings required to be distributed with a returned 2018 contribution will add to your AGI.) Otherwise, take a regular distribution in 2019 of exactly the amount of the excess (with no adjustment for investment earnings or loss) to eliminate the excess for 2019.
If the code PJ 2018 Form 1099-R has no tax withholding shown in box 4 there is no need to enter it into 2018 TurboTax and TurboTax will ignore it if you do enter it (except to remind you that it was reportable on your 2017 tax return).
