When she was in season for the first time last year, she went frantic trying to toilet, running in circles, whining/yelping when toileting, and looking at her bum... Second season is just starting, bang on six months later. Yesterday & today she has walked round and round the garden wanting to toilet, but not going - I'm assuming because it's painful? I can't think of any other reason why she wouldn't go when clearly she needs to.

Anything I can do to help her? I can't bear the thought of her being in pain every time she needs to go Should I take her to the vet?

There's no doubt that for some, when the vulva is significantly enlarged, they must be able to feel it but I've never had what you are experiencing with your bitch re trying to toilet.   Yes, mine tend to spread it around more (urine) but that's all.   Are you talking about urine, or stools?    In any case, given what you are describing isn't anything I've seen, it might be worth getting your vet to take a look.  Just in case.   Keep her in the car and not in the waiting room!!

If she is just starting I wouldn't expect massive changes in her vulva or enough to cause what u describe.does she get constipated during a season or could she have a utI as not sure if u are e feeling to poo or wee or both.I agree with mama nas worth speaking to your vet

Yes I will call the vet - I thought some other bitches would experience it too, but clearly not.