This does indeed mean that you are the Squad Leader. As Squad Leader, you have the functionality (or obligation if you prefer) to assign squad tasks. This basically amount to attack/defend a certain point (you get bonus points if your squad then complies).
If you are squad leader, you can set an objective by pressing the "spot" command while targetting the objective.
Also certain servers only allow people to spawn on a squad leader, but a squad leader can spawn on any other squadmate.
Sometimes the game will "forget" where certain points came from, and award them under additional points.
For example, I just received 2820 additional points BUT my jet score said that I'd scored 0 that round, but I'd actually scored the exact amount that I received in my additional points. It only forgot for the after round tally, as when I checked my vehicle tab, it remembered my actual amount of jet experience (I'd levelled up).
So it seems the varying amounts may be due to for instance, it not remembering that you got a particular ribbon, or a particular service medal.
Here's a video explaining what I mean. It's pretty bad quality, but as you can see, my jet score shows up as 0 when it's tallying points, and I gain 2820 "additional points". Then later when I switch to my vehicles tab, jets has +2820 experience.
Also, as of Back to Karkand (and I'm assuming future expansions will do this too) any assignments you complete will award you 5000 "Additional Points".
Additionally, any XP earned during a double XP weekend will earn you the same amount of XP extra under Additional Points.
Best Answer
It seems like it's bugged (or unimplemented). Others are reporting the same thing. If you're throwing out medkits and getting points for healing your teammates, and it's still not moving, it might not be enabled.