Never seen those knickers, but your dog should lick herself clean, we never had mess around the house- or on ourselves.
You can get something, sorry I don't know the name, to disguise/hide her tantanising scent and, there is treatment via the vet for the morning after 'the event'. Left too late it's not a good idea, although doubtless vets perform late abortions - but dogs only take about 2 months. This is for next time - not long either - but, spaying is the best solution.
Hope by now the pups have found good homes- it's a shame to hear of so many strays & so many put down & so many people allowing their dogs to breed & even thinking they can make a profit out of this. Sad to think you got caught here by an animal charity.
regards
tegwini
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