Root canal should not be painful at all. You do need to be fully numb, so there are a couple of injections at the beginning which register 5 out of ten for discomfort. After that you need a little time for the injection to “soak in “.
Root Canal can be done over more than one visit if you need to go slower.
Sometimes you get a bruising type low grade ache 3-5 days following root canal. Normal headache tablets will resolve this completely.
Dont forget to let your dentist know how you are doing, if you feel its a bit of struggle, they may be able to change tecnique.
Rob