Welcome to Yorkie Talk! Do you have someone nearby that has
experienced whelping a litter or two before? If not, the best advice
I can give you at this point is to keep the vet's number
and an
emergency animal hospital's number handy. Emergencies can
happen quickly (trust me, I've been there).
Many years ago my vet gave me the best advice while expecting
my and my maiden mare's first foal
..."one of you needs to know what you're doing". 
Sending you and Bella my best wishes for a happy & healthy litter!
