is she pregnant?

Question
my dog zoe is a choc lab she is a little over a year. she has been in heat once that i know of. we also have another lab that is a boy and hes over a year too. he has tryed to have sex with her but we are not sure if it worked. her boobs are alot bigger than normal well bigger than before she went into heat the first time! we are not sure what to do, can you tell us if she is pregnant and what do we do?

Answer
She may or may not be.  A month after the mating, and vet can tell.  the swelling could just be a false pregnancy.  They are quite common in young Labs.  

Likely the vet won't want to spay her until the swelling goes down.  There is no good reason to keep intact dogs unless you are a serious breeder.  We are slaughtering millions of dogs a year for lack of homes.  Much of the problem comes from accidental breeding and those not doing the extensive work it takes to do it right.  While I don't buy the idea that nobody but show people should be breeding, everybody needs to be doing all the health and temperament testing.  For more on this, see http://www.woodhavenlabs.com/articles.html#breeding