Should I be concerned about this?
Yes.
This should be of concern to you because an attacker was able to obtain the valid password for your gmailGmail account. From the details of warning you have provided, it looks like it is from fraud detection rather than an OTP failure. If it was an OTP failure, you would have received an OTP when that login attempt was made (unless your OTP delivery mechanism is not email or SMS based).
You should explore the chances at whichpossibility that your password may have leaked. Do a search on HaveIBeenPawnedHaveIBeenPwned to see if any of the websites where you have used that email waswere compromised. It is likely that you may have used the same password for signing up to a trivial service and forgot all about it.
The the intention of attacker was not to use your email to enroll these services, rather it looks like an attempt to verify if you are a user of any of those services. Most sign up options would ask you to login instead of sign up if you have an existing account with them. From the looks of it, the attacker wanted to identify the services you are already enrolled to with that email and wanted to try the same password on them.
To sum it up again, yes you should be concerned. You should explore why you are being targeted in the first place and how that initial password compromise may have happened.