Hi there
I was coming on here to post almost exactly the same question - my lo is 4 weeks tomorrow, and only ever feeds for 10 mins at a time. After dd1, who would take 20-25 mins each feed, this has been something of a surprise. I have been concerned that she is not getting enough, as she seems to want feeding every 2 hours, and I have been trying to get to a 3-hour EASY without any success.
We have recently started to manage some 3 hour stretches at night, though - during the day I quite often give her a second feed about half an hour after the first to try to persuade her to go for longer - maybe this could help you as well?
It's good to know that there is another lo out there doing exactly the same thing - even down to the completely unpredictable naps!
Good luck.
Clare x