"You look so pretty!"
*Did they mean that or did they clock me and they were just being nice?*
You know you can just choose to believe them, right? And even if you can't, someone choosing to be nice to you because they clocked you is not a threat or an insult. Take the compliment and enjoy it, because after a lifetime without, you deserve it today.
Edit: didn't think I needed to say this explicitly, but realized I probably do-- You can easily be clocky and still be pretty. Trans is beautiful.