Hi, Mikro
Welcome to Microsoft Community.
I realize that you've received an email from yourself in New Outlook for Windows.
Please do not worry, it sounds like you received a typical phishing email designed to intimidate you and scam you out of money. Such emails are usually scams designed to intimidate you into paying a ransom. Do not respond to the email and do not make a payment.
Verify that the sender's email address is exactly the same as yours. Often, scammers will use similar addresses with minor differences. We have found that many users have encountered some fraudulent or phishing emails sent by hackers and also modify the sender's email address. You happen to be in this situation as well.
Methods to view the sender of an email:
1 Select the email, click the “....” of the email.
2 Select “View”, “View Mail Source”.
3 Find the location of the following picture in the mail source, this is the original IP and sender.
Once you find it is phishing email, you can choose to report it: Phishing and suspicious behavior in Outlook - Microsoft Support
Apart of that, please make sure you have multi-factor authentication enabled on your email account to add an extra layer of security.
Anyway, such emails are usually bluffs designed to intimidate you. Ignore the threat in the email and don't let it get to you.
Best Regards,
Cece | Microsoft Community Support Specialist