Awake Since 2am!!!

I woke up last night (this morning) at 2 am and it's now nearly 9 o'clock in the evening. That's 19 hours and I'm still wide awake. I take Mirtazapine which is a sedative so when I take that, it knocks me out. It used to knock me out till about 10am the next morning, but since I've been really underweight it doesn't have much effect anymore. I just hope I don't wake up at 2am again tonight. Other nights I've woken up but been able to get back to sleep. I think I had trouble last night because I had a bad dream.I've had my milk again today. I weighed myself this morning and I think I've lost weight but I can't be certain because I'd drunk 3 mugs of tea during my hours of being awake. So with my last mug, I weighed myself before I had it, and right after to find the difference...then just took it off my weight 3 times....no I'm not obsessive at all   0_0I hope I can sleep tonight...it's weird but I seem to be more energised at the moment and kind of 'hyped up' that I have been when I've slept quite well. Any explination for this would be appreciated because, well I *shrugs*