Breathing fast when I pat my rabbit.

Hello, this is my first post, I'm quite new to indoor rabbit owning. (My rabbits get supervised outdoor time every day. Our house is connected to a nature reserve here in Australia where snakes frequent our yard)

My female mini lop has been described as a diva by a rabbit sanctuary vet turned private breeder when adopting my second rabbit. Not sure if this is a favtor. But thought I might as well add it.

When my boyfriend and I let her out for her free roam time indoors, she honks, jumps, runs around all that jazz and comes up to us for pats. As we pat her (stroking chin to ears) she goes into what we call "hen mode" and starts breathing rapidly. When we stop she stops the rapid breathing and looks at us. We pat her again she goes into hen mode and rapid breathing starts again. When I looked this up, it says nothing besides "your rabbit is stressed or scared." I'm worried that I could be doing the wrong thing. I don't see anything about a rabbit being happy when breathing fast. She doesn't seem distressed in the slightest. I'm more than happy to accept that I'm doing the wrong thing so I can improve but I would like to know what I'm doing wrong. So feel free to be on the negative side. I just want my rabbit to be happy.

I have a large English spot and he does the same, though he will slowly relax his breathing. Not sure exactly why, but other times he doesn't do it at all, quite the opposite. He'll slow his breathing, close his eyes and take a 5 minute nap while I pet him. Now if I was to pick him up and carry him, he'll get stressed and pant like crazy. It'll take a little time for them to get used to all the commotion so the breathing should relax eventually if it's just stress and not some medical condition.