I'm extremely stressed out and don't know if I should quit my current internship. Thoughts?

Embrace the first part, you are whipping yourself up, into a frenzy, because you're high-strung(nothing wrong with that). Let-go of this : "I know I should calm, but I cannot. I also sleep lots of hours but I keep having nightmares so I cannot even rest" Because that's how you turn healthy-stress into Anxiety.

You shouldn't be calm, you need to be prepared, and ready for action, so jog, ride a bike, play basketball, or swim(whatever physical activity you like, do 30-60 mins every day, until you start your internship), and you need to recognize that it's an adventure, so you'll encounter problems you don't have an answer to, ASK when you do, because that's why it's an internship, you're there to learn, to develop. Most people make the mistake these days that excitement needs to be repressed, or contained, that's why so many more people get anxious these days, embrace the excitement, use it, to DO, that's how you perform.

I cant really gove you an answer,but what I can give you is a way to a solution, that is you have to find the anglde that you relate to or peaks your interest. A good paper is one that people get drawn into because it reaches them ln some way.As for me WW11 to me, I think of the holocaust and the effect it had on the survivors, their families and those who stood by and did nothing until it was too late.