Hi Judith - I echo Pammys advise to get a copy of The Perfect Puppy, it is brilliant

Nothing you have described to me sounds like anything other than a perfectly normal pup - at 9 weeks old puppies don't know what aggression is; all they know is play and loads of it

Take the example you gave of coming up the steps when you have left her alone in thegarden, for instance. Her natural instinct is to return to safety out of this big scary open space, once she has done her business

Crying is her way of telling you (her protector) that she needs protecting

Standing on the steps and preventing her coming in won't help - as she will interpret this as a game - pups play by barging and pushing against each other. Hand clapping will excite her and she is far to young to understand what the word NO means at this stage - all she knows is that you are talking to her

Growling and nipping is the way that 9 week old pups play -when together they learn not to by discovering that when they nip too hard, their siblings yelp and end the game. Playbiting may go on for several months - Gwen Bailey expains how to use a time-out method in her book which really does teach them.
Time is a great tool for conviniently "forgetting" things - if you had your Westie from a pup, I am sure that it went through typical puppy behaviour too - I would be more worried if it hadn't. You are right; hitting a puppy will teach it all the wrong things about people and can eventually lead to a dog that may snap/bite in fear

No point in shouting either; pup doesn't understand what you are saying, just that the noise you make hurts it ears

Have a read through the Puppy section of the forum: as Caroline says, we have all been at the end of our tether and in tears - and we all came out the other side, a bit bloodied and scarred, but with a great doggie friend by our side

Good luck