i wonder if this is something going around... blossom woke me up early the other day with a gurgling tummy (i've never been able to hear it before) and needed out... as soon as she came in, needed out again. This went on for a couple hours. I gave her half a pepcid, and when we finally got back to bed she jumped in beside me and wanted snuggles (absolutely abnormal for this dog!!). You could tell she felt pretty bad.
Yesterday, merlin and murphy had the same problem.
Not saying your dog has the same thing, just relating a similar issue that's going around my pack.