Well, congratulations on your new puppy. It's a shame that you have to worry about this.
Watch your puppy for lethargy and check his gums - if they are pale, he may be having hypoglycemia -- keep a tube of nutrical on hand in case this happens. Make sure he is eating regularly.
As to potty training, unfortunately, it really does take awhile. Sometimes when doggies get excited they let loose of a little urine - could this be what is happening?
I'm by no means an expert, but I hope this helps a little
We'd love to see pictures of the little guy! What's his name?