Get a wrist splint. I sleep in them because my hands get bent up under me and it causes me to wake up in horrible pain.

contact yoiur professor and due to the circumstances see if you can't sweet talk him.

I bought wrist braces online through Amazon. The company is Actesso. I'd advise getting a size larger than you need as the Velcro ruins your clothing if it's not completely covered. Why would they not allow you to use braces? If you can't get OK to use braces in time perhaps you could buy one of those grips that go around your pen and makes it larger so you're not having to grip so hard.

I also used splints and I used both of them every night or my hands would hurt, I finally had some carpul tunnel surgery from a neurologist, He would only do one wrist at a time, He told me that usually if you do one you don't need to do the other one. He was pretty much on target, Of course he didn;t give anything for pain. I had some at home. He was an ass. He thinks he was the world should bow to him. He did a good job though