My daughter (7) still does this from time to time. If I go to her and try to wake her up, I just get a drowsy smile. Well, sometimes I get her grumpy face, when she's very sleepy and doesn't appreciate the lap in her eyes LOL
My youngest son does it pretty regularly. Last night, in fact, I got a bad case of the giggles in the middle of the night when I woke up from a bad dream, knowing I'd been talking in my sleep, to hear my husband whimpering slightly, the baby fussing to himself, and the dog growling and "running" in her sleep! It made me wonder how any of us get any rest in this noisy house LOL
As long as she's getting enough rest, I wouldn't worry too much about it. It may be that she's going through a big developmental milestone, and her brain is working out the details while she's sleeping. It could just be her way of releasing tension, or it might just be a "thing" she does sometimes. It could be some discomfort, like teething or stuffy nose/ears/sinuses from allergies, a little cold or something of that nature. Does she wake up stuffy? Have any sign of an ear infection or other fluid in her ears?
Night terrors last a lot longer than a minute, and are very, very loud, and really creepy. Both of my kids were prone to them, which is unsurprising, since I'm a sleep-walker, and the two are related somehow (in this case, they seem to be related by blood LOL). The crying is usually more like screaming and thrashing, and, even if the eyes are open, no one's home. I can also say that night terrors are harder on the parents than the kids, since neither of mine ever seemed remotely upset after one, while I was shaking and clammy for 30 minutes afterwards!
Check what else is going on with her (ie teeth or learning a new "trick") and go from there. If she's teething, a little medicine before bed might help her rest easier. If it doesn't seem to bother her, try to let it go and not be bothered in yourself. Kids do weird things sometimes, and, as soon as you have one figured out, they find a new weirdness to worry you with! LOL
Good luck!