Most likely no. Unless you saved it it’s gone. That is one of the primary reasons I do not use notepad for important documents. If you had done any copy / paste you may be able to recover what ever is on the clipboard. That is as long as you have not rebooted the PC which would clear the cache.
There is a free tool Note Tab Light. It has an auto save feature to prevent losses in the future. Launch the program and click VIEW > OPTIONS then in the middle is a check box for automatic save and you can specify the number of minutes to save your work.