meaning of "puff things almost humorously out of her way"

[KuaiLe]

I’m reading "Too Much Happiness", a short story based on Russian mathematician Sophia Kovalevsky by Alice Munro. In the story, Sophia was taking a tiresome train journey. A doctor-passenger gave her a tablet, saying, “This will give you a little rest if you find the journey tedious.” She had a sore throat and was coughing for running to catch the train. After she swallowed the tablet, the story goes:

"Sophia has never been drunk in her life. Any medicine she has taken, that might addle her brain, has put her to sleep before any such disturbance could happen. So she has nothing with which to compare the extraordinary feeling … At first it might have been just relief …she had survived the fit of coughing and the squeezing of her heart and been able somehow to disregard her throat. But there is more, as if her heart could go on expanding, regaining its normal condition, and continuing after that to grow lighter and fresher and puff things almost humorously out of her way."

I’m confused about the last sentence. How can one’s heart puff things out of one’s way and do it “almost humorously”? Can anybody explain the meaning of this sentence for me?

 

[Tarheel]

Thanks for the context. Unfortunately, the phrase seems to be totally original. My best guess is it's something in her imagination.

(I assume you meant she was coughing after running to catch the train.)