Hello SLH071070,
Yes, you can sill file a tax return for 2018 and you should do so. Sounds like you may be entitled to the Earned Income Tax Credit and possibly the Child Tax Credit. Both of these credits are refundable, so even if you had no withholding on your W-2 you could still get money back when you file your 2018 tax return.
Review the following information provided by the IRS on these topics:
https://www.irs.gov/credits-deductions/individuals/earned-income-tax-credit/eitc-income-limits-maxim...
https://www.irs.gov/help/ita/is-my-child-a-qualifying-child-for-the-child-tax-credit
I hope this information helps you.
Thanks,
Jack
