Nightmares or Night Terrors??

Its just that, except i think the name is geared more towards parents than the child. Possibly the scariest thing to witness.

Where do i start?...

This night time waking was happening quite a bit; she'd wake up fussing, whining, whimpering. By the time i was out of bed it was crying. By the time i opened her door it was screaming. As i reasched her crib screaming turned to screaming, crying, blood curdling whaling! Eyes open, sitting straight up she sees me and throws herself down into her bed screaming louder. I try to calm her but rubbing her back, she fights and resists. Atempt to give her some milk, the swats and it and throws it, still screaming. Then i try to pick her up and she almosts flies out of my arms and throws her self around her bed until she has her head burried into her pillow off to the corner. This whole time shes crying out "Mommy! Mommy!! Mommeeeeee!!" & i keep saying "Im here Leah, Mommy is here. Its ok!" But its like she cant hear me, & shes just so completely confused- she doesnt know what she wants. At this point i didnt know what else to do but to walk out. The screaming continues, and gets louder. I cant take it. Its only a min, if that, and im back in there trying to comfort her somehow. Eventually i force her to come with me in my arms. I sit in the rocking chair with her and hug her while she continues screaming and crying. Finally, my patients are wearing thin and i kinda lose it. I raise my voice and say "Leah!! Thats enough, stop! Tell mommy whats wrong." (She doesnt usually tell me- per say but she almost always points to what she wants). She stops crying for just a moment. 5 seconds comes to an end and its screaming again and now pointing out the door. I say "Do you want to go out?" She screams even louder! Occasionally i will take her out of the room and walk around with her in my arms. It never goes well when i sit back down again, whether it be in her room or mine.
Some nights i rock with her until she goes back to sleep, other nights i bring her to our bed. Both times thative brought her to our bed, Matt has left and went to sleep on the couch since he gets up early for work. So its just the two of us. She lays around, stares around, for SO long! I'm talkin 90min- 2 hours! Neither of us get much sleep on these nights.
Its just come to attention that this could possibly be night terrors, so im not completely sure what could be triggering it, if this is what it is.
Two days ago she had a nap at 2:30-4:45. She usually naps at 1-3(:30). I knew she wasnt going to be tired when bedtime rolled around but i wanted to stick to her routine, so i started her bed time routine at 8. We brrushed teeth, had milk during stories, said prayers, say a few songs then just rocked for a while. A long while. 30 minutes passed by and she was still wide eyed looking around. I continued to rock her for another 15-20 minutes. She was still wide awake, but laying in my arms and cuddling comfortably, occassionally sitting up then laying down again. After an hour of rocking her i stood up and put her in her bed. She started to cry. (No, im not too happy that i had to let her cry for ten minutes but i had to BREATHE! I wasbeyond frustrated and i didnt want to take it out on her) --(Que argument with Matt [thats another story])-- Ten minutes passed and i went back in. Rocked her somemore and she finally was tired enough to let me put her in bed about 15-20 minutes later.
This was the last night that she woke up with what i believe to be a night terror! So, im thinking... forced sleep may be the cause?

Sister-in-law's son had night terrors for a short period. (At least thats what she called it, i think he just  bad night mares) She told me that Leah was too young for Night terrors. I did some reading and some research. Turns out, shes not too young. Night terrors can start as early as 18 months & ive even heard of some cases even younger!

Last night it took about 45-60min to get her into bed. But she did NOT wake up.

I'm really looking for some feedback here so if you have any advice or if you can tell me weather you think this is night terrors or nightmares, i would greatly appreciate it! If there is something i should be doing to help prevent this, please let me know! I don't mind waking up to comfort her, but when she wont let me? Thats frustrating, and heartbreaking.