Did you ever get them before? I get them from even breathing too deep, so it doesn't surprise me to get them after major surgery in that vicinity. The swelling could be stimulating the nerves and causing it.
I wouldn't worry about it but mention it to the surgeon next time you see them. I know how annoying and anxious they can make you feel, when I first started getting them I thought it was only a matter of time before I had a heart attack but years later I'm still here and barely give them a thought now.
GERD, Anxiety, Depression, Rolling Hiatus Hernia, Esophageal Hypersensitivity