on the sheetrock got lifted when the paper was removed. It's common to occur when dry-stripping the top layer to make wetting down then removing the backing easier. There's a water-based product made by Zinsser called Gaurdz that was made just for that problem. You cut out the blisters with a razor knife then apply the product. Once dry you patch the areas, retexture the spots if needed then repaint. Zinsser's website will have all the info you need.