You should probably have drained a little more since you can always add some back in.
Now keep driving for a while to see what the measurement says. I think you are pretty safe at this point.
Overfill light came on out of nowhere...about 700 miles after TTC repair at dealer. When the light came on I knew for certain it had not been overfilled so I assumed it would go away when I started it up the next day. Nope! Still there when I started it up... until I drove for about 20 miles and it went away. Will be interesting to see how often this happens.
Incredibly annoying. Out of warranty 18 days, of course.