Don't beat yourself up over this. I assume you're in high school? Or middle school?
You'll forget about this in a short amount of time. Besides, you decided to change the answer back, so who cares? This is such a menial problem, it's not worth stressing over AT ALL.
If your teacher knows you cheated, apologize. It's simple, not like you're the first anyway lol. I used to do the same thing in 7th grade, it wasn't ever a big deal to me.
(If you're in high school, it's a bigger deal, so try not to cheat or anything if you're in high school. When you're a senior, you may need on of your teachers to write a letter of recommendation. They might refuse to write you one if you cheat a lot) Lastly, what class is it?
I have teachers that grade you for actually trying to do the homework, they don't downgrade you if you get an answer or two wrong. Maybe thats how your teacher grades? If not, one wrong answer won't affect your grade, if you're worried about that as well.
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.