Distress on Indiantown (Pt. 2)

Jess stopped at Maddie's house, and said goodbye to someone now invisible to her. She didn't hear a response either. She let out a long sigh, and pulled out of the concrete driveway. She drove out of the neighborhood, and came up on the Walgreen's to the left. The traffic light was red, and she was at least not insane enough to drive right through it. She looked to her right at Johnathan, who was placidly looking out of the window. The thunder roared in her head as the light turned to green. She didn't let off of the brake, but instead doubled over with a splitting headache. She saw that neither Johnathan or Rebbecca would even speak to ask what was wrong. Neither of them were even looking over at her. She was going insane. This was proof. She wasn't even sure she had left the beach a few minutes ago even. None of this was normal. Her brother and sister were never so apathetic as to leave her doubled over in pain. Her world spun with thoughts about where she was and what was going on. She might of been at the beach still, or in her bed asleep. Maybe she actually was here right now with thunder at surreal volumes in her head, and uncaring siblings. She managed to look back up at the traffic light to see it was red again. Thankfully no one was behind her. Her headache subsided a bit, and she looked for the light to turn green. It did, and she drove. She felt dizzy. She began to overcompensate for the wheel alignment, and ended up careening down Military. She couldn't stop. She suddenly found herself face-to-face with a palm tree.
Strange. Palm trees didn't belong in the road. Of course, cars didn't belong in the median did they? She suddenly panicked. Johnathan Rebbecca! Were they okay? She looked back. She looked, but didn't see anything. Were her eyes closed? She forced them open. She still only saw black. She looked back ahead, the palm tree was still there. Nothing else. She kept her head forward, and felt for her seat belt. It was still there. That's what she felt, not what she saw. She was not calm in the least. She couldn't think. The only thing she seemed able to do was hyperventilate, and stare at the palm tree.
"Okay." She told herself. "I'm dreaming. I'll just wake up soon, and things will be fine. My family will be back, and I'll be in my bed. Come on, just find a way to wake up."
She began to feel sweat. She turned. She felt attacked. She didn't see anything. Her mind was being attacked, but she knew she was dreaming. She woke up, and tried her best to stifle a scream.

When I first heard of "night terrors," -the nightmares some have that are so horrific that when they wake up, they can't seem to remember what they dreamed about, or even if they dreamed, they could only remember that they woke up scared to death- I had wondered what it was people dreamed about that was so horrific. It's probably worse than what I thought up here, but I just guessed. What is it that could be so horrifying that they wake up in cold sweat with a scream of terror? It scares me trying to think about it.