You've got nothing to worry about, bro.You're just experiencing the usual winny induced jaw growth.Once your jaw size increases by 30% the aching will subside...
I just started winny tabs a few days ago and my jaw was cramping last night. Of course, that was after eating some pussy for a half hour, so that might have something to do with it.
jaw lines are effected by growth hormone. i've cycled for years with no change in my jaw or facial features and yes potassium while on winny is a must. The only time my jaw bone changed was at a competitive bodyfat and that was caused by severe diet.
while on, I get intense pumps in my shoulders on bench days, biceps on back days, and the arches of my feet as well.
I am going to try taking potassium next cycle to prevent some of this.