Started first mead with little/no information. Should I intervene now?

Yep, it will be very dry and not a lot of people like dry mead, but that can all be fixed. Once the fermentation is over and you've "stabilized", you can then add some honey to the sweetness that you like.

Of course, because you didn't feed your yeast, do any degassing or temperature control, it will not be drinkable for several months

Yep, read the NewBee guide, watch the Meadology series, on YouTube, by The Canadian Sasquatch (he just made the 9 episodes into a book) and pay particualr attention to episodes 6 and 7. Also, start listening to the gotmead podcast series, on Modern Mead Making, starting on September 5, 2017. You can find a link for them under gotmead radio, on the home page.

Not sure if you should bother with nutrients at this point. With EC-1118, your fermentation is probably close to being finished. FYI - that yeast is notorious for fermenting too aggressively, thus losing aroma and taste.

Start learning about Fermaid O (or Fermaid K) and rehydrating with Goferm. Check out meadmaderight.com.

If you don't have one, GET A HYDROMETER and learn how to use it. There are plenty of youtube videos on how to use one.

Opening and working on your mead will become a common practice and as long as you use some common sense, clean and sanitized equipment, you should be fine. Opening up could let contaminants in, but it's rare. Don't cough in it! Use common sense.

From what I've heard, EC-1118 is a powerhouse. It will probably eat through that amount of sugar pretty easily and not require too much intervention on your part. Without a gravity reading, you can't tell how far along this is, so my guess is that it will finish without any problems, but I am still new so some more experienced people might come in here and correct me.

You shouldn't really be worried about taking measurements and opening the fermenter. As long as you are sanitizing everything then it's only a very small risk. After fermentation you need to be mindful of not adding oxygen, but it's also nothing to panic over.

My (newbee) suggestions would be to let it sit for a month, swirl it every couple of days to try to keep the yeast in suspension, and then rack to another vessel to get it off the yeast cake on the bottom and begin the clearing process. Worst case scenario: you have to let it age for several months to smooth out.

Hiya Miabeewood - and welcome.
A couple of quick thoughts: most of the anxiety around fermentation comes from brewers and not so much from wine makers. Grain, you see, and so beer is incredibly open to bacterial "infection" Grain is covered with lacto-bacteria - and lacto bacteria can sour beer (literally). Think lacto fermented pickles. But to sour vegetables you need to add salt to both encourage the lacto bacteria and discourage other organisms. Honey (and fruit) does not seem to be so susceptible to those organisms and both the levels of acidity and alcohol tend to kill volunteer organisms so whereas brewers bang home a bung and avoid touching their brews until they are ready to package wine and mead makers tend to be far more laid back, view degassing (by stirring) their meads a couple of times a day as standard practice, and view taking gravity readings through-out the active stage of fermentation as a non issue. Indeed, as long as your sanitation protocol is up to scratch (perhaps use the sulfur dioxide produced by K-meta as your preferred sanitizer rather than the cleaners that brewers use) you can happily return samples to the primary fermenter with no care or fear.

While I very strongly agree that you need an hydrometer, you can in fact easily calculate starting gravity close enough for playing horseshoes if not archery or darts. One pound of honey dissolved in water to make a US gallon will raise the gravity of the water from 1.000 to 1.035. Two pounds will raise the gravity to 1.070 and 2.5 will raise the gravity another 17 points , to 1.087. A starting gravity of about 1.087 when fully fermented will give you a mead with an ABV (alcohol by volume ) of about 11.5% (my rule of thumb: multiply the starting gravity - finishing gravity by 131. For horseshoes that's good enough). Good luck.

Hydrometer !hydrometer!Hydrometer.
Yeast nutrients at all?
temps?
Did I say hydrometer?