Sorry to hear what you are dealing with. There are a lot of people who have similar symptoms without an answer.
All I can say is that you take the bull by the horns, be strong and hope that everything turns out to be ok. The neurosurgeon is going to need to get that cyst out if your head for one, especially if it's causing pressure. 2 he will need to do a biopsy to make sure it's malignant.