I am in a similar situation. I just tried the "Get My Payment" process at IRS.gov and this was the reply:
"The information you have entered does not match our records. Please try again."
"If you used information from your 2019 tax return, the return may not have been processed yet. Please enter information from your 2018 tax return instead and try again."
The reply implies that they will be making the info from my 2019 return available for qualification for the payment. So I plan to wait a couple weeks and try again. If you would not qualify under your 2018 data and have recently filed your 2019 taxes, I suggest you do the same.
PS: I also read that we have all of 2020 in which to establish our qualifications for the payment.
PPS: Here is a Washington Post article with some useful information about significant dates for the process: https://www.washingtonpost.com/business/2020/04/27/more-1200-stimulus-checks-are-way-here-are-key-da...
