toothache during pregnancy

Two adjacent molar teeth; one has a porcelain cap after a root canal done 4 years back  the next has a filling...but i started noticing a slight pain during flossing between
those two teeth;so the dentist removed the filling and put a temporary filling on that teeth; said if the pain starts we will have to check with an x-ray and will have to
do a root canal...got pregnant during that interval..and started noticing a dull pain in the crowned teeth!...is this a referred pain??? the temporary filled teeth doesn't hurt
when touched but the crowned teeth does...the denstist said she wouldn't take any x-ray during pregnancy and said she would remove the temporary filling and leave the teeth opened
if it hurts. I am not sure if that teeth is causing a problem...is it possible for the root canal treated teeth to get infected again...i am currently 37 weeks pregnant...i can wait a
couple of weeks i guess..but i am in pain...what should i do???