I agree with you that you can just look at your heart rate because the two splits were the same time. Sometimes the GPS on watches can get a bit wonky.
You could share a link to your Strava workout if it’s public (you can check the privacy settings for the workout).
The fact it felt easy is a good sign. If you feel like you could go out and do it again day after day that’s also an indicator that you are working under AeT. Do you know what your AnT is?