I should've put the childcare costs on my return since I'm the lower income earner.
Did you prepare you and your spouse's returns together? And did you enter "any" childcare expenses?
No worries. Happens to the best of us! 🙂
Please read through the article below which provides details on how to make adjustments to your return with the CRA.
https://turbotax.community.intuit.ca/replies/2647992