What Causes Excessive Sleepiness Along With Poor Memory?

For the past 6 months i have had been experencing random sleep episodes where i fall asleep at work, driving, at home and i have no urge to sleep. Also headaches for the last 4 months stress makes them worse. Also i have pins and needles in my legs and there are days that i sleep for 8 hours and i wake like i didnt sleep. There are alot of times i cant remember or i have a issue trying to say things like its there i just cant get the words out. i recently had a mri done for my headaches and results showed abnormalities in white matter had blood work done to factor out lymes diease and was neg.