You do not even know if you filed a 2017 tax return? Then first check to see if the IRS has a transcript of a return you may have filed.
You can get a free transcript from the IRS:
https://www.irs.gov/individuals/get-transcript
**Disclaimer: Every effort has been made to offer the most correct information possible. The poster disclaims any legal responsibility for the accuracy of the information that is contained in this post.**