SD or Newbie play?

Game 14682021
I'm curious to see what you guys think, does this look like secret diplomacy or a newbie mistake?
Rounds 1 and 2 they hit each other to take bonuses. (With blue's first attack the only one not going for the bonus he DID take). Red took Washington and Blue took Nevada with me going for Oregon.
Once it was clear I was between them I moved away from Oregon and into California, however the attacks did not stop. From rounds 3-8 I was the ONLY one they attacked even though I had half as many troops as either of them.
On round 8 blue took me down to 1 territory and red took it and then they fought it out until Red won.
So what do you guys think? Newbie mistake going after the weak lieutenant or Secret Diplomacy?
I'm curious to see what you guys think, does this look like secret diplomacy or a newbie mistake?
Rounds 1 and 2 they hit each other to take bonuses. (With blue's first attack the only one not going for the bonus he DID take). Red took Washington and Blue took Nevada with me going for Oregon.
Once it was clear I was between them I moved away from Oregon and into California, however the attacks did not stop. From rounds 3-8 I was the ONLY one they attacked even though I had half as many troops as either of them.
On round 8 blue took me down to 1 territory and red took it and then they fought it out until Red won.
So what do you guys think? Newbie mistake going after the weak lieutenant or Secret Diplomacy?