Your Vit D may be a factor, but not the entire cause.

So start taking some D3, 5000IU daily and get retested. Now that summer is coming, you might get by with 2000IU daily, but that is dependent on how much sun you get daily when the weather is nice.

Your thyroid numbers are getting iffy esp for a young male. Something you should get retested. Canada has different concentrations reported, and you need to find out how they compare to US numbers. In US there are two scales now, .01-3 and .01-5. The second one is being dumped in favor of the first one for TSH levels.

There are thyroid mimics in the polluted environment now, and they contribute to hypothyroid being more common in males than before. Some are fire retardants in bedding and clothing and furniture. So this problem is getting more attention now.
You can Google it and see for yourself.

I see in your profile you are a fisherman? Did you get toxins and heavy metals done at the doctor's? The Great Lakes have limits on how much you can eat per month of large fish. Trout, Whitefish and other game fish. So you might have some heavy metal issues, that need testing.

Having stiff hands is the beginning of arthritis for some people.
That feeling is very common among us. You might investigate antioxidants, and fish oil, for their anti-inflammatory actions.
They really help. I am using the new Krill oil, and also use "smart foods" that contain Omega-3 s and this helps me alot to keep mobile. But good old quality fish oil works well too.
Grapeseed extract, is a good antioxidant to try. 300mg a day really helps some people. Good for allergies too.

Thanks for the update. I hope your finals are over and the stress is less now for you. That stress can't be helping...