Getting mad at her, when she gets excited and pees
will only make matters worse. I might be wrong but isn't this a sign of submission?
Our little terrier use to Pee every time we came
home or when she greeted others.
We ignored her for a few minutes when she did this.
She did grow out of it when she reached around 1 year.
Her and Rocky took a good 4-5 months to potty train too,
compared to our other dogs
who took less than 3 months.
Each dog is different, so just be consistant
with the potty training and never leave her in the house unsupervised while she is a pup, or it will
take much longer to potty train her.

I am sure you will get some very good advise from others
on this list. Just don't get mad and have patience,
remember she is just a baby.