It sounds like "night terrors."
Its purely developmental based and crops up from about this age.
BOTH my kids had that, when they were about that age.
Research it online... you will learn much about it and what to do when it happens.
Night terrors are different from "night mares."
But, if she is just waking due to night terrors and then she is not going back to sleep... then she is REALLY already woken up, fully. The thing with night terrors is, you don't want to 'wake' the child up... but let it process on it's own, and they usually fall back asleep. Otherwise, the child will indeed fully wake and think it's time to come out of the crib and 'play.'
So you have to gauge her.
BUT also at this age, they are changing a great deal, and they do wake more at all hours, to 'play.' It's a child's form of insomnia/sleep difficulty. Their motor skills and sense of 'awareness' is changing too. BOTH my kids went through that too, at that age. So, what I did is... IF this is the case, I just pretended to 'sleep' and gauged them. If they could just entertain themselves fine in the crib or next to me... then I just let them. I did NOT engage or interact with them... and just kept saying 'sleep, shhhh..." and that's all. I stayed lying down, did not get up, did not turn on any lights... KEEP everything quiet and dark. Make things BORING. Then, my kids would go back to sleep. On their own.
This is a phase and it will pass before you know it. She's young and they do this about this age. My Pediatrician said they also have some separation anxiety at this age too. So it may play into it.
I did not punish or scold for it. It's a developmental thing. Now if your child is perhaps hungry, you can feed her. About 12 months old, they have a big growth spurt as well.
The thing is, it sounds like night terrors to me, because of the way she is waking up screaming/crying/hard to calm down. But that does not mean you have to "wake" her up at this point. When having night terrors, the child is not really 'aware' or 'awake' and knowing what they are doing. So keep everything dark and try not to speak or get her aroused to the point of "waking." Just comfort. Silently.
But read about it online and it will tell you what to do.
All the best,
Susan