Root Canal...Now it's sensitive to COLD. Arg.

Some of you may remember me talking about my root canaled tooth being sensitive to hot. I went to the dentist and they put me on antibiotics. It started feeling better within a day. Now, 1 week later, with only 5 days left in my treatment, my tooth has become sensitive to cold, and much more so than it was to hot. It is quite painful for a good 30 seconds after initially being touched by the cold. It doesn't even have to be ice cream cold...just chilled and I go through the roof. It's also become much more sensitive to pressure. I can't eat on that side now. I can't take off more work to go back to the root canal guy but it's looking like I have no options. My dentist is open on Saturday but he won't see me again for this because he says I need the specialist in case the root canal needs to be repeated.

I remember phoenix saying something about this and the cold being a cavity and the hot being a nerve. I can't have a cavity, can I? That would be horrible...I am not sure what they would do since I have a permanent crown on.

Anyone else deal with this? My mom had to go have the ends of her roots capped off. I can't remember what its called but I am starting to think that I might be having the same problems she is having....I am seriously being bummed out by this.