Lost where i was and /back didn't work

There was a castle I was making for an hour and a half. I took a break to help someone in /plotworld but when I did /back it brought me to the location I was before I was making the castle. I forgot to set a warp to it also. Is there anyway you can figure out where I was so I can get back to the castle I was working on for over an hour straight? Thank you

Nvm Gloomer fixed it