Hi I am a first time mum and my DD is now 12 w...

Hi I am a first time mum and my DD is now 12 weeks old. When I feed her the bottle it usually takes about an hour, this hour consists of feeding, burping every now and again and sometimes a nappy change. Is an hour average or is it too long? The reason I ask, is I only noticed it more when I was at the mall in the parents room, I started feeding DD and so many other mums came in fed their babies and left and here I was still sitting there. I know though that when the feeds are that long, DD finishes her bottle and is full, that way she does not trouble afterwards. Just wondering if anyone else feeds for the same amount of time. Thansk