I don't want to further stress you out but seeing/hearing/glimpsing things that are not really there is, in my opinion, a major issue. I feel like I know what you are talking about, I've done hallucinogenic drugs and not had ANY hallucinations. But I have had them while sober and/or under the influence of psychotropic medications.

It is something you should talk to your doctor about as soon as you can. In the meantime you need to do everything possible to reduce your stress level. As a society we are addicted to, and even brag about our stress level.

Being anxious doesn't get you through the reading and writing any more efficiently. The problem isn't that you SHOULD relax, it is that you actually NEED to relax, stress is more harmful than most people usually think it is. Think about the difference between responding and reacting. Cut yourself a break, step back, zoom out, take some time to breathe, whatever it takes to separate yourself from the situation.

I remember the stress of mid-terms and finals but for the life of me I can't remember any specific assignments. And that was less than five years ago. Big picture those things don't really matter, take care of yourself and try to get through it, but taking care of yourself matters a lot more than grades or passing your classes.