That’s unfortunate. It makes it harder to find the original when too many unsourced copies get reposted elsewhere, and then the original creator doesn’t get the credit they deserve. An easy way to keep track of image sources is to add source info into the file save name such as the OP’s name and the site it was saved from.

I took some time to find the original, looks like the OP was nshnv on reddit: https://www.reddit.com/r/itookapicture/comments/12riaq6/itap_of_tokyo_during_the_rain/