Since getting Thistle back in November she has not been her usual self, although she hasn't been suffering (outwardly). She would run and play with Guinness but not nearly as much as she used to play, and she has been more distant with me. I was hoping it was just part of readjusting to being back with us after 5 months apart.

Saturday afternoon she sat bolt upright in the middle of napping and just started screaming. That only lasted a few seconds. Then again on Sunday during a nap. She is completely naked while in the house, so no collar or harness to bother her. Last night she had another attack around 1:30 am, this one lasted about 10 minutes, and then she was clearly distraught but not screaming for several hours afterwards. I barely slept at all (she slept about 2-3 hours, and otherwise was so uncomfortable that she was pacing around and barking at things.

I thought to get a video, so I've uploaded it to YouTube.
This was the 1:30 fit, the video is only of part of her panicking.

I have contacted a vet here about getting immediate attention for her, but otherwise is there anything I can do to make her more comfortable?

From the vet I asked for a cortisone shot to get her comfortable immediately while starting cimitidine or omeprazole.

The other thing I'm thinking it could be is a disc/spinal injury if someone dropped her or she had a fall while she was out of my care for the last 5 months. So we'll probably start with an X-ray, and a work up before going for an MRI.

Even though I always knew this could happen, it's so upsetting to see my little girl so distressed, and it just came up so quickly. She's been reserved, but not showing pain. I feel so terrible for her.