I noticed in my emails that I was being sent things to a weird looking Apple IDs
Looks like you use Hide My Email, see the following Apple articles:
What is Hide My Email?
What is Hide My Email? - Apple Support
Learn more about Hide My Email and iCloud+
Learn more about Hide My Email and iCloud+ - Apple Support
Hide your personal email address in Safari on iPhone
Use Hide My Email in Safari on iPhone – Apple Support (UK)
Create and manage Hide My Email addresses in Settings on iPhone
Create and manage Hide My Email addresses in Settings on iPhone – Apple Support (UK)
Turn off Hide my Email -> Manage the apps that you use with Sign in with Apple
Manage the apps you use with Sign in with Apple – Apple Support (UK)
and I was worried someone else had my account,
Check ⤵️
See who has access to your device or accounts
See who has access to your device or accounts – Apple Support (UK)
If you think your Apple ID has been compromised
If you think your Apple ID has been compromised - Apple Support