New account over the old lost emails

I somewhat foolishly (in hindsight) put my old emails from my old work (Default Account) account in a folder called old. I then changed the account details in the Default Account to my new jobs account info, thinking they would still just be in the same place.  But by by changing the account details it appears that my old emails are now gone when Outlook synced with the new email account. Are my old emails recoverable in any way?