Unknown email address during Steam verification?

Hello, I was just about to play a bit of gaming when I got a message from Steam saying I had to log in again. I wrote down my password and everything else and typed it in exactly the same way. Suddenly it said the password was wrong. I tried all the possible passwords that came to mind but nothing worked, so I clicked on I can't log in and wanted to reset my password. When I wanted to enter my email address which is linked to the account, it said that this email address did not exist, so I did it using my username. When I then wanted to reset the password, I suddenly got an unknown email address, "t*********@r******.r*". I have already written to support but only received the automatically generated email and was told that I would receive an answer shortly. However, I have a bad feeling that someone else is gaining access.

to my account and I would rather not lose the account. What is the best thing I can do now?

Thanks