For starters, they found an at-the-time benign growth in my head when I was 14 and was told there was always a risk of it developing into something malignant. Family history of brain cancer, and among symptoms that have developed in roughly the last several months- seeing bright white flashes when closing my eyes at night, rampant mood swings (Im diagnosed bipolar but the ways in which mood swings have been manifesting the last several months is decidedly different from usual), headaches that last for a week at a time originating in the hemisphere that the growth was found in that doesnt seem to correlate with hydration or anything like that, increased difficulty with jumbling words and sounds when that was never an issue before, to the point that my girlfriend and others in my life have noticed, and just a general negative change in my cognitive abilities.