Congrats red! XXX
Girlygirl, I know we are about a day apart but I went thought this at about 6-7 weeks! I would get in from work, sleep for an hour or two, then get up have my dinner and be in bed by ten and sleep through again until 6am. It is wearing off now, and although I am sleeping from 10pm til 6am I don't need my afternoon nap anymore! I know how you feel though, it is crap. I couldn't concentrate on anything.
I really found that having a little nap helped, otherwise try bananas - they're full of energy.