Oh good gravy!!! When my boy entered adolescence he mostly experimented with rank, dominance, etc. What this looked like is he started aggressing against dogs he had never had a problem with and he kept punking dogs (they would be focused on someone or something else and Zeek would walk up to them and pop them with his muzzle), and a lot of air snapping at dogs that came into his space. Basically he was a snot. Sorry, I love him, but he was.
He experimented a little with ignoring my commands, but that wasn't too bad. A simple leash at all times and he gave that one up.
The rank experiments resulted in a few things:
1) He lost his privileges at day care (he used to be able to go on morning hikes at day care, but one of the dogs he was challenging on was the resident male).
2) Because you didn't know who he would take offense to or how he would react, we also muzzle trained him and when we hike, he walks on a 30 foot training lead.
3) Leashed when we were in the backyard in case he tried to blow me.
4) EVERYTHING was worked for and he had to "ask permission" for everything (get on the sofa, get out of the car, etc.)
We are getting toward that time when he may enter his second snotty phase so we're bracing for that, but the tell me second one last less time and is less intense. ...here's hoping!
On a side, but related note, at this same time, he had some physical pain that caused me to take him a holistic vet who does acupuncture. After a couple of treatments, he seemed to settle down and just generally come more relaxed and more "forgiving" of dogs being in his space or bumping him. I don't know if the two are/were related, but it all seemed to get a noticeably easier after he started acupuncture.
Best of luck and be sure to let us know how it goes!