Hi JosieJo,
Try to treat the FS like any other place - we would not accept a tyre shop or restaurant adding on an extra fee without discussing it with us - so don't feel as though you accept it from a fertility clinic. I would ring explain what has happened and say that you asked for a quote before you went and were never told at any stage there would be any other charges. They are all required to provide fee costs, and yes of course in a perfect world you would have checked before paying the bill - but that isn't a reason to charge you for something that was never mentioned.
It's NOT the norm to do what they have done at all BTW - and it really doesn't matter if it counted as a consult or not to have your partner with you - it was never discussed as an extra charge and therefore is not appropriate to charge after the fact