Hello, first of all I'm glad that you are brushing twice a day, but brushing without flossing is not going to help you in preventing future cavities.
You need to start flossing either use a conventional string or waterpik (if you are afraid of the gum bleeding).
Next is you need to get a comprehensive check (using x-rays) up done, to check the status of existing fillings and missed out cavities.
Once all this is sorted, the pain and discomfort will surely reduce.
Also ask the dentist about the right brush and technique.
Oil pulling is not yet proven as a valid modality to prevent cavities, sorry.
Next Steps
Visit nearby dentist for complete dental checkup
Health Tips
Watch YouTube videos on waterpik.