You can look up night terrors on webmd or other websites. My daughter is also 2 and started that a couple of months ago.
What seems to have worked for her (at least for now) was
1) talking to her about happy things and telling her that if she had a bad dream, all she had to do was think about happy things (her tricycle, making bubbles, etc.) and that would chase the bad dreams away and
2) she got a new stuffed puppy so I told her that "new puppy" would protect her from the bad dreams and growl and chase them away. She also sleeps with her favorite blanket and lovey.
It took a lot of repetition, especially the first part, which I'd repeat every single night before I left her in bed and if she woke up during the night with another dream, but it seems to have worked now. I still hear her call out in a bad dream from time to time, but she can soothe herself back to sleep now. Good Luck to you.