getting dizzy then passing out

i give a little back ground . i am 36yrs old and have alot of health problems . i started having grandmal seizures as a young child. my seizures are lasting longer about 4-5 min and use to have them while sleeping , now anytime. my breast started leaking and found that i had a pituitary tumor. my tumor grew to 22mm and had a crainotomy in 06, im still tumor free. i got bloodclots after sugery and had a tulip filter and it couldent be removed. i have chronic daily migraines / icepick migraines and cluster migraines. now for the past 2 yrs i have been getting dizzy and passing out. i got dizzy and passed out and came to covered in sweat. i have been dizzy off and on for 2yrs. i got dizzy and passed out sat it was different. while i was out i could hear and couldent talk or move. i was only out for a min but it was scary. when im dizzy it doesnt matter if i lay down or walk or just sit im dizzy the whole day. it does make it worse if i look up. im not on any new meds and im worried . any ideas whats going on? please help !!!!