I hope you're doing well.
This is Hudson from Meta Support Pro.
Thank you for providing all details about the situation. We really understand how importance has this matter for you since you probably have this account for a long time.
Even though we don't have direct access to help you with this profile situation, we will do our best to provide you a guide properly on how to recovery your account.
In such situation you have to recovery your account by following one of the steps below:
1 - Please do logout from any other profile that you are logged in on the computer
2 - Report this hacked situation directly with the Security Team here:
https://facebook.com/hacked
3 - Select the better choice on the form to provide the Security Team your exact situation
4 - After selecting the options the system probably will ask you some questions to you regain control of your account
Note: If the email associated with your Facebook account has changed, you can reverse this. When an email is changed, we send a message to the previous email account with a special link. You can click this link to reverse the email change and secure your account.
Here you have more resources and information about the matter:
https://www.facebook.com/help/203305893040179
I hope this clarifies and at least bring some good insights about this matter for you.