I had a Golden that had a fetish for paper items in the trash and socks…
and were at the vet for blockages 3 times with her - all socks.
This dog would eat any food you gave her, and so the biggest sign was not only when she would refuse food, but when she would drink tons of water and then throw up the water. When that happened, she was too dehydrated to pass the sock, and I took her to the vet to be put on IV, and fortunately, she passed the sock each time once she got hydrated.
ALl that to say you must get the xray/ultrasond for a blockage.
"Female" items would be a different story, so I would go get her checked as soon as you can.
Female items are made to absorb liquid, which is NOT good in a stomach or intestines.
Hydrogen peroxide was a life saver a few times with her, when I caught her having just eaten a leather jazz shoe, or a padded bra, or... ballet tights... (After a couple of hours, using it would be too late...)