I USED to experience same exact thing, but i FIXED IT!!! Yahooo and you can, too. I also have family with MS... my dad, aunt, cousin. Not only that, but we have a whole slew of other autoimmune disorders amongst all close relatives... like over 10 major disorders... but I am fine :) So here is what is happening. You have to start stretching the muscles in the back of your neck and do isometrics. Tight muscles that are not stretched cause all kinds of weird problems. So you need to do the stretching along with isometrics for the neck every day. By keeping the neck loose, you will also loosen the jaw, so you will no longer grind your teeth. Don't chew gum. That will inflame the TM joint and therefore cause a clenching reaction. THe tension headaches you are getting (you have classic) behind the eye and back of head, one side only... that is caused from the tight muscles in back of neck because that is how the nerve path runs and ends. The brain cannot feel pain, as it does not have the ability to. So if you feel pain, I always tell people it is not brain it is either nerves or muscles but commonly muscles because they can feel pain and refer it to other areas even. Adjust workspace, and wear glasses if need be. THe flashing lights... that prob is from either ocular migraines, caused by rapid dilation/constriction of veins behind eye... or lightheadedness from getting up too fast, or a little dehydration (twithcing can also be from that). If you have pain behind eye and see lights (of course if it's severe pain and lightning bolts then get to doc rright away)...you need to work those tense muscles in the neck which will help to even control the veins.. put less pressure on them. I aslo have twitching... its called BFS... and certain techniques I have been doing has helped it so it's not nearly as bad as it used to be... There is an easy explanation for what ails you and it is all coming from the neck muscles!!!