Wagging Rat?!?!?

Question
I have had my two pet rats for about two months now and they're really starting to open up! Then one day I was petting one, Roy, and as I was petting him he was wagging. I also have three dogs and thought maybe it was like a happy dog wag but then when I stopped and picked him up he squeaked! It sort of sounded depressed but I wasn't sure. Do you think this wag was a sort of warning and then the squeak was fright or was it all enjoyment? I read on a website once that some rats do wag and it's very cute but I don't want to put them in any distress! Thanks for any help!
               -Danielle

Answer
First off, I'd like to apologize for such a late response, we've been having internet problems. The first thing I thought of after readin about your situation is a female rat in heat... When they're in heat, females tend to vibrate and/or wiggle their ears when touched and can be twitchy and squeak. Are you absolutely sure that your rat is male?