Based on your reply, most likley Microsoft has a record of your update to Windo0ws 10. You can download an ISO of the Windows 10 installer. This can be placed either on a DVD ir a 8 GB USB stick. (Presently it is under 4GB, so a 4GB might work.)
You will need the use of another computer to get the download. I assume yu will use the 32 bit version. I the Windows 7 was the home version, you should use the home version of Windows 10.
The Windows 10 installer might be able to recover your current installation and thus save your photos and other personal materiel. It should also keep any programs you added.
You can take the Windows 10 ISO from the Microsoft site. Or you can also try this:
http://www.redmondpie.com/download-windows-10-pro-iso-file-without-product-key-from-microsoft/Microsoft has clearly attempted to make sure that all bases are covered as far as installation options are concerned. Although the company started initiating pre-downloads of the operating system to registered PCs approximately 24-hours before the official launch in late July last year, it does appear to recognize that some consumers would require an official ISO image of the Windows 10 platform whenever the need to manually install or reinstall the OS on a formatted machine arises. The ISO image will of course allow for the creation of a bootable USB flash drive or DVD, to serve as an installation source.
It is legit. Microsoft will know if you cheat.