Should I Get Rootcanals / crowns ?

Hi I really need advise....
I had 6 white fillings done in a good dental school, some of them were very big and the teacher/student told me that those tooth could in the future at any time need a rootcanal.
These teeth were fixed around May. Although they stay senstive, I use mouthwash, sensitivity toothpaste etc., some moments I feel nothing, sometimes an annoying light constant pain, variating to sometines a bothering pressure-pain, but on the other hand, now I am totally fine (an hour ago it did hurt).
I don't know what to do. I am a traveller, so I don't want to be stuck somewhere and have an emergency. Maybe I sould just get the rootcanals/crowns done?
Now I can go to a dentist, and after a 3 weeks trip I could go again, but then I am moving to another state.
My question now is, should I just go in? The dentist took x-rays and didn't see anything, but he said that if it is bothering me I should do rootcanals/crowns for the 2 teeth that hurt (they both have huge fillings going to the dental pulp).
I don't kow though, an I definately going to be fine after that? And as I will be moving, are most crowns fine right away? Because I won't have the option to go back to the dentist to adjust.....

Please help me out... this is very hard!
I also rather do it now, than be worrying with every slight pain I feel, the dental school did really stress on it that those (and some other too) teeth are sensitive for root canal etc....

Thanks for any ideas, what would you do?