had a cow sluff a calf about a month ago.took her to the vet. he could find no reason for her to abort. found the calf by the way about as big as a fist.the cow had afterbirth and just looked like she calved. I just assumed it was her fetus.figured about 3 months along.my question is, could she be pregnant with twins and just abort 1 or did I make a mistake which cow it was because now she is bagging up and starting to spring pretty heavy.