What Causes Memory Loss During An EEG Test?

Hello. I m a 25 year old lady who s 5 1 1/2 and weights 132.8. I just went to the doctor to get an eeg done. During the middle of my eeg; I lost my memory. I couldn t remember where I was at or what was going on. It was REALLY scary. I wanted to ask the lady what s going on, whats on my head, where am I, who is she, and more. I felt like I was panicking. I made a noise. The lady looked at me. But I stayed still. I can t remember the rest well. But then what felt like a few minutes later, it happened again. But not as scary. Both instances it came and then went. There was no fading away. It was all so sudden. Is this normal to happen while their testing your Brian waves? If not; what does it mean?? Can you help me? I m worried. :(