If the pain appears mainly when you lie down then you may have a cracked tooth.
The pain will get worse and last longer with a cracked tooth.
Oh I have been there... cracked it on a rock that was at the bottom of some dried beans and missed it when I cooked them..never again..I check them real good.
Hope the oil pulling works.
I think castor oil is perfect..why not, it is one of the best oils, flax second and check out the olive oils for the best..there is a BSA on cz on olive oil reportings.