I know I am not an INTP, but I wanted to post anyway and I have extremely low F & J scores.
I have been seeing a therapist for a year and she refuses to diagnose me with anything other than depression. She says it is for insurance purposes. She is a very nice lady.
I have always thought I had social anxiety dissorder and I have to make sure I force myself to go hang out with friends at least once a week. I do see people at work and stuff, but it is not quite as uplifting as hanging out with friends.
I would definelty do a nutritional evaluation for the headaches and neurological issues. Make sure you are getting all of your vitamins, minerals, enzymes and phytochemicals. This and exersize help me.