Hello, Last night when I was trying to go to sleep I kept on having these very weird sensations, like I was sinking or fainting. These episodes would jerk me awake just as I was drifting off, and would occur every few minutes. They definitely weren t hypic jerks, these were very much like the feeling you get before fainting and were quite scary. I couldn t get to sleep for about three hours despite being exhausted. I woke up feeling quite dizzy, and like i was not up-right as I walked around, even though i was. This went away during the day but now in the evening I still feel a bit unstable and dizzy. I am a 23 year old woman, I have PCOS, not overweight, I don t smoke and haven t had a drink in about a week. Can significant sleep deprivation (which is what i ve had for the past week) cause weird sensations like this? I m not really stressed or anxious about anything in my life right now, so I am not sure if this could be related to anxiety (I have struggled with a mild form of this in the past, but I feel fine at the moment) as I have read about. The only thing I have changed lately is taking vitamin B supplements due to a suspected B12 deficiency - these made me feel much better for the past week but thanks to last night I m wondering if they could be the culprit here? I had a blood test and my blood pressure checked about three weeks ago (was diagnosed with irritable bowel syndrome), and everything came back normal. Any insight into what could be the cause of these sensations would be greatly appreciated. I am very tired and just want to go to sleep, and not be concerned about what s going on with me. Thank you!