Well you are probably upset and rightly so after being rejected, anyone would. Don't take being labelled 'too quiet' to heart. They actually did you a favour as it prevented you being in a situation day after day where people ridicule you for being quiet, instead of handing it to you professionallly.
So now you know that other than that you are impressive to them, well done for that. Again try not to think about this emotionally. So what you are quiet, you know you are, that is something you need to work on if you want to, otherwise you can accept that's just the way it is and keep going to interviews until someone thinks that a quiet, hardworking person is more important than a loud mouth who disrupts everyone.
Out of curiosity, what was the job you went for?