ive been on zoloft since last tues. and started taking 50 mg since friday... it just started today that i can't sleep at all literally...like when im right about to fall asleep i feel like im falling and my arm twitches and then i wake up...ive tried going to sleep about 5 times but i got this everytime...it's really scary.....is it bad to go a night without sleeping?? please someone reply.