starting to get nervous

Im looking for some advice... my cat Izzie is pregnant and i know when she concieved. Today is day 66 of her pregnancy and still no kittens and no signs shes about to have them. how will i know when they are coming and what is the longest she should be pregnant... I called my local vet and she said they usually are pregnant for an average of 63 days so im starting to worry that something might be wrong since its now day 66. I have never had a pregnant cat before and i plan on getting her fixed once this is all over but since its her first pregnacy im being extra cautious with her. any advice or help would be greatly appreciated! thanks

65 days from first mating is the average.  By day 70 it becomes something to worry about.  She is well? 

she's very well... extremely loving and eating a lot still... the babies are very active inside her... i can see and feel them and everything seems to be going perfectly. i just figured they would arrive this past weekend and when they didnt it got me starting to worry. How will i know when they are coming? i know the mother will get very vocal  as they start to arrive but are there any signs i can watch for that lets me know it'll be happening withen 24 to 48 hours?

Some mothers dont get vocal at all.

But the first sign you may see is her losing her mucus plug around 12-24 hours before.

Dont worry, everything will go well Im sure in less than 4-5 days you will be here saying how cute your kittens are