Did a fresh install of Windows 10 on a new SSD, no activation

I upgraded from Windows 7 to 8, and I no longer have the key for 7. From Windows 8.1 I upgraded to 10. Recently got an SSD, wanted to do a fresh install on it. Used media creation tool to make a USB copy. Booted from USB, formatted old hard drive, and loaded Windows onto new SSD. I picked activate later as the product ID i wrote down did not seem to work; and assumed it would auto activate.

Well, now Windows is not activating, and I still cannot enter the Product ID, I assumed that would be the "key".

Is there anything I can do at this point? Or am I just screwed and have to buy a Windows 10 license?

...I knew I should have just cloned.

Found a Windows 8 key in an email from the upgrade, and it accepted that. Please lock thread.