L.Q.
Yes sounds like separation anxiety all right! My son went through this before as well but we just put him in his crib after the bedtime routine told him we loved him and we'd see him in the am. Then we'd walk out of the room and stayed out and let him cry it out. A few times I would have to go back in to let him know we were still there and finally after about 2-3 nights he got over it and fell asleep again no problem. However several months later it happened again so be prepared! But just do what you did before and let her cry it out. I have a wonderful and very helpful book called Healthy Sleep Habits Happy Baby by Marc Weisbluth, MD best book I ever received as a gift!It will all work out just be patient and buy the book!
Good luck! Also I agree with what someone else said it could be an ear infection (not likely though) or teething! My son had a horrible time teething especially at bedtime. Try Hyland's homeopathic teething tablets. You can get them at CVS, Walgreen's, Riteaid, ect! They work wonderfully and calm them right down with no side effects or worries about liver damage like Tylenol or Ibuprofen can cause.