wow 3 times a day with coconut oil is A LOT! No matter how healthy you are, you would have some die off effects of all kind of pathogens and nasties including candida. If you had infections and candida overgrowth, the headaches and the worsening of the symptoms means your body is struggling to keep up with a die-off effects.
I also started with coconut oil, and I would swish with it once but sometimes twice or ever three times a week. The first few days I was full of energy and telling everyone how amazing it feels, clean mouth, clean head... and then it started. a week of feeling so lifeless, as if I was run over by a truck.
And I was healthy to start with, on a good diet, but clearly my body had so much to deal with. When I think of it, I used to have sore throat and sinus infections quite often. Not any more, since I started pulling i was only sick once and the infection was gone, and I mean GONE in a day and a half with nothing but vit c.
let your body do the job, support it with good nutrition and vit c, lots of water and be patient.
The symptoms mean it is working.
the white teeth are the bonus.
Oil pulling won't solve all your health issues in a week, but it is still the cheapest and most powerful single remedy (ok, maybe with an exception of high doses of liposomal Vit c ) to improve your health all around.