Weird sensations when falling asleep?

I am a college student who has suffered from GAD pretty much my whole life. I’m also a massive hypochondriac so I am well aware that the stuff I am experiencing is most likely related to these fears, yet I am still afraid I have a serious neurological illness or something. From around the end of November I went through a particularly stressful period due to uni- had to study for a test and write a very big thesis. The test was in mid December and the same day it passed I had my first night of insomnia. It was horrible and lasted until the 19th and afterwards I got about 10 days of completely normal sleep and minimal anxiety. That was until the night between 29th and 30th where I couldn’t sleep at all once again. So far this week 30th to 31st has been the only good night I managed to sleep but I think it’s bc I was with my boyfriend. New Years Eve night when I was back home I once again got 0 hours of sleep and was an anxious mess the whole New Years Day. This night thankfully I managed to calm down my anxiety before bed and fell asleep quickly, slept for around 4 hours but I woke up at around 3 am and didn’t feel tired until 4:30. However when I tried to fall asleep again a bunch of new scary sensations started that once again have me on edge. First of all I feel somewhat of a light dizziness/vertigo, as well as brain zaps which I only got during the day until now… then there’s a lot of hypnic jerks and twitches, feelings of chills around my neck and head and the weirdest symptom- sensory hallucinations. Most of them are auditory like loud noises and people speaking, but I also had a couple of ones where I felt like something is brushing against my arm or nose, or even pulling me? There was another one where I thought I felt my leg lift up for a moment. Sorta feels like I start dreaming before I am even asleep. I am aware that the stuff I am describing probably sounds insane but I really need to know if anyone else has experienced anything similar… I just managed to calm my heart down and all of a sudden all these weird things start happening whenever I feel myself drifting off and startle me awake once again. I am scared it’s due to something big and serious but I hope I can chalk it up to anxiety, because I have a friend who has went through my issues but now she can’t relate to the current problems I am describing and I feel my anxiety creeping up again :’D I am so tired.