Hi Gillian

What you describe sounds like what my clinical neuropsychologist referred to as confabulations, which are inaccurate memories or perceptions ranging from subtle alternations to bizarre fabrications. I had a number of these as an inpatient, some of which I remember, but they quit a few weeks after my accident while I was in neuro rehab. They can be caused by disruptions in blood flow to areas of the brain affected by the injury. If you are seeing a neurologist or neuro psychologist I'd make them aware of this.