Unfortunately, The IRS is not processing mailed in returns at this time. The following is from the IRS:
The IRS is not currently able to process individual mailed tax returns. If you already have filed via paper but it has not yet been processed, do not file a second tax return or write to the IRS to inquire about the status of your return or your economic impact payment. Paper returns will be processed once processing centers are able to reopen.
All you can do now is keep checking the IRS website, Where's My Refund, the website updates once a day.
https://www.irs.gov/refunds
