How does score reporting work?

Since I am taking the SAT and ACT in the fall, I was told to write which schools to send them to automatically, especially for early decision. I am confused by this, because what if I end up doing worse than what I currently have? I know this is (hopefully) unlikely but things happen. I’ve tried to google about this but nothing comes up (sorry if this is a dumb question). If I choose not to to this, will my scores not be ready in time for the ED deadline (Nov 1)?

The scores will be ready at the same time. The additional time is for you to decide whether to send or not, send $ to the testing agency, have them process the $ and send out the scores. That adds at least a couple of weeks. You’ll need to check the dates on when scores need to be at the college to see if you have can make that happen. Schools will sometimes state what the last test dates are that would be acceptable.

They say the last possible time is late fall but they don’t say whether or not that includes self reporting or if it’s directly sent from collegeboard. I’m assuming they’re saying its directly sent. Do you know what happens if your score ends up being worse? Would they just look at the previous score or would it hurt my chances?

You mention you will be applying ED. That means you know which college since you cannot apply ED to more than one. Which college? Someone here may already know its rules for ED.

Northwestern

Northwestern superscores the SAT and will look at your ACT scores from the test date with your best Composite. You shouldn’t worry about getting lower scores. You can hold off on automatic reporting to non-ED schools to give a little more control.
http://admissions.northwestern.edu/apply/tips.html#StandardizedTesting

My only problem is that its my first ACT score and also that I’m taking the SAT subject tests

Through last year, Northwestern accepted test scores that arrived after Nov 1 and even accepted through the November SAT test for ED, see, e.g., last page of Open Mind’s brochure from last year, http://admissions.northwestern.edu/documents/open-minds2015.pdf, although it wanted that test sent blind in that you needed to designate Northwestern in your November test registration as a college to automatically receive scores upon release (that results in the fastest form of delivery). I am unaware of any change for this year but it changed all its pages relating to applying and I cannot find a definitive statement for last test date accepted. Probably it is just an oversight but you should likely call or email the admissions office to get definite answers.

As to what happens if you send multiple tests, Northwestern has for as long as I can remember used your highest test scores for admission and not use dlower scores against you. It superscores the SAT (although not the combination of an old and new SAT; if you submit both of those it considers to havre the higher composite), and for the ACT uses that test with the highest composite, And if you submit both ACT and SAT, it uses that test it believes has the higher score.