Celexa Panic Attack, Panic Attacks, First Night, Pills, Brain

Hi,

I've been taking Celexa for 3 weeks. The first week I was taking 10mg, then 20mg. After almost 3 weeks, my doctor prescribed me 30mg, because I wasn't really getting better. The first night I took 30 I was fine, but last night, I took it again and had the WORST panic attack ever. I was almost hallucinating. I've had panic attacks during the first week, because I was so scared of the pills, but now I thought I was ok with the idea. So I don't understand why i had such a big attack, when I haven't had one for 2 weeks... all of a sudden. Could it be the bigger dose ? Will I get used to it ? I'm so scared these pills are going to take control of my brain... as soon as I feel the effect too strongly, I tend to panic. Could it be just thtat ? Thanks for your help...