Uh....not the worst, but still large enough that them getting aggressive is a TAD problematic. 😅
As far as the bite goes, you should ro ehat Johnny said and get someone to look at it ASAP. Dog bites aren't fun, and it sounds like it was fairly deep? Clean it as best you can with what you have available (do you have a basic first aid kit?), wrap it so you're not bleeding all over the place, and then get someone whose actual job it is to deal with it take a look. Friendly reminder that dogs literally eat shit, among other things. Lol. Not something you want to leave unattended if you can help it. You up to date on your shots too?
As far as the little lad or lass themselves......there are lots of reasons an animal can get aggressive, and some are salvageable, and some......aren't. Whether they've hurt themselves/BEEN hurt by something, or are sick, or whatever else.......kinda hard to tell just from this. At least if they're pretty young (I think I saw you say they were 2 somewhere here?) then you can generally rule out some things. Like the poor things mind going, for example. Seen that happen sometimes with older dogs, and they got dangerous.
I also had a dog once who damaged her back, and her response was to crawl into a corner under a bed and sit there snarling at anyone who came close (fortunately she was on the smaller side, and we managed to get her bundled up and to a vet without causing her too much distress).
What was going on when the Lab snapped at you?