Sometimes, when I am feeling a bit blue, it can seem like the most necessary thing to do is to worry or stress. Instead of doing that, I try something else: thinking of my future self.
When I look back, I see exactly how little my worry mattered. My worry did not make tests or interviews any easier. If anything, it made it harder for me!
I look back and see a lot of my worry as wasted time. Instead of worrying, I could have taken steps against my worry (studying or researching more), worked on something else, or just (plain old) lowered my blood pressure.
It can be hard to look outside of the circumstances we are in, but everything is temporary. Think of how you would want to look back on these years.