My friend had her dog mated on the 20th of july, she is still slightly swallon but she keeps licking herself all the time, theres not discharge and her vulvas not hot, she asked the vet and he said since there is not discharge and its not inflamed then not to worry but shes starting to irrate the skin from the constant licking? is the vet wrong should she get a second opion? could it be a sign she is pregnant? opions much apreciated.

my bitch is in season and she's always licking herself

Have you checked exactly where she's licking? If she licks so much that the skin is getting sore, something isn't right.Could it be she's having troubles with her anal glands? It's normal for a bitch to lick herself after a season, and also if she's in whelp, but if she's licking so much it's irritating the skin, I'd ask the vet for a new checkup.
Good luck with the litter,
Karen