It is a really long test. You might already be doing this, but improve your endurance by doing all sections of a practice test in one go. I think we get 15 minute or 20 minute breaks in between each section. The JLPT website has two practice tests so you can practice doing all the sections at once.
Listening is the last section of the exam. If you haven’t already, look up N3 listening section. If I remember correctly there are 9 questions where there is nothing written in your test booklet. It is just a blank page. All questions and answers are spoken (once) and they are pretty fast. It is definitely something you want to practice. Listening is my strongest section, but it was challenging to do this at the end of the exam.
I took the practice test on paper in almost one go, had to take a few breaks during. I let myself move on to the next section even if the allotted time hadn’t elapsed, though. I did the listening section too (with the blank page questions) and I scored well, so I’m not too worried about that part. I’m definitely going to do ~2 more practice tests before December.
The feeling of depleting the lesson pile without rushing is a nice one! I’ve only got 7 or 8 vocab left in the pile for now, but I’m probably leveling up tomorrow and there’s still 38 items to unlock in this level so I won’t enjoy my clean work surface for long.
It’s possible you ran out of lessons for the combination of your level and the kanji you’ve guru’d. The basic flow of WK is when you move up a level, the radicals of that level are unlocked plus any kanji that only consist of radicals you’ve previously guru’d. When you guru a radical, it unlocks any kanji in that level that use that radical. Likewise, when you guru a kanji, it unlocks vocab in that level using that kanji.
At the start of the level there’s generally a mix of locked and unlocked kanji and vocabulary so your progress doesn’t entirely stop - plus of course, to move up from level X to X+1, you have to guru a certain number of kanji, so you’ll have also just unlocked vocab in the level you just left.
But, yeah, that “huh, I could do lessons, but I guess I don’t have any” can be nice. I was going to have that but I did guru most of the kanji I’d need to level so I’ve got a healthy vocab pile again - with a couple more days because I also missed enough kanji to stick around a few more days.