housebreaking/leash training

Question
Hello Labman!
My family recently purchased a new Pomeranian puppy about two weeks ago.  Her name is Molly.  We believe that she is 4 months old, even though the pet shop owner told us that she is two months old.  
We have had about 4 dogs over a span of 15 years but yet this one seems different from the others.  She is more quiet and calm and seems shy at times.  
My question for you is about housebreaking her.  She sort of has the idea when it comes to going on the paper, however, whenever the leash is attached to her collar she freezes up.  She will not walk on the leash at all. Inside the house or outside.  In fact she will pull away from you whenever you try to pull/coax her towards you.  Furthermore, when she gets outside, she shows no interest in using the bathroom or being outside period.  She doesn't get excited or even sniff around at all.  I will take her outside after meals when I know she should be ready to relieve herself and she will just lay or sit on the ground and look around as if she's being tortured and wants to go back inside. Sometimes she'll just stand there.  I've tried coaxing her with treats, toys, etc.---but nothing has worked.
I am hoping that you have some kind of advice to help with this problem.
Thank you so much for your time.
Sincerely, Leslie

Answer
If she is 4 months old, she should be in the middle of getting her adult teeth, having the larger front teeth, and a mixture of large, small and gaps in the back, and the tiny, sharp puppy canines.  

Socializing a puppy that lived in a pet store until 4 months may be a challenge. Perhaps the leash and outside together are too much.  You might try her outside off leash.  A fenced area would be best, but likely she is too small to outrun you in a large open area away from traffic.  Give her some time, stay close, but far enough she has to move to come to you.  A ball could help.  If she does start to move around and then has an accident, lavish praise on her, and maybe give her a treat.  

Keep working with her on a leash inside.  Perhaps just leave her loose in the house with a short leash on.  Let her get used to it.  Most puppies will respond to being pulled by the leash by starting to walk before long.  Others, you must coax.