Itchy, kinda painful tooth/gum with filling...

Please excuse me if I am lacking insightful information in this post, it is the first time I have ever posted on this forum.
I have a tooth that had a filling done a few years back, at the time it didn't hurt but the dentist said it had a crack in it and would probably get a cavity in it. After the filling was complete, the tooth actually hurt when exposed to various semi-extreme temperatures such as hot tea and ice cream. I told the dentist about this and had it looked at and was told that there was an exposed nerve and that it would fix itself... I switched over to sensodyne toothpaste eventually in hopes that it would reduce the pain and it did. The filling itself is very bumpy and is in no way smooth, the dentist knew this and tried to fix it but didn't do a good job.
I've ignored it until now... I don't really know if I should go into the dentist or not. I'm slightly terrified that they may have to perform a root canal on it since this itchy, painful feeling has been going on for about 3-4 months and I can't really bite down on that side of my mouth. I guess I'm wondering what any of you guys think is going on with my tooth/gum.
A slight complication is that I've left it a bit late to want to do something about my tooth because I leave for a out of country vacation in a little over a week and would only be able to book an emergency appointment before I leave, but if I don't go in and am in a different country and suddenly have the worst tooth ache of my life or something I'll be stuck with an advil diet until I returned back to the US. :[ But still am wanting to avoid going to the dentist unless I absolutely have to...

Hi and I think you know you really can't avoid going to the dentist before you go away, I don't think an exposed nerve with heal itself. I would get a new dentist when you get back, but in the meantime get an emergency appointment before you go.

I may be talking out of my backside here but this doesn't sound right at all, and I think that being in pain tells you this is not okay. A filling may need time to settle a bit if they are deep but 3 months is a bit extreme I think. Maybe a dentist will be able to help more than me and explain better for you, but if it were me I would be running to a different dentist to have the filling put right. Your dentist sounds incompetent to me, he should at the very least be able to smooth the filling down for you.