Hello Do you have cold , if yes this insect feeling could be because of that. As in cold there is water collection behind the ear drum ie middle part of ear. You must consult your ENT doctor to confirm the diagnosis If there is insect inside the ear then you will have to get it removed and you will require a tetanus injection also to prevent yourself from a disease called tetanus. There is need of injection as a  preventive measureas because the insect spores on its skin and you may get the infection from the insect Don't panic just go and consult an ENT surgeon to get the correct diagnosis. Just pouring the oil will not help