My overtime at work and I (Should I stay or should I go?)

I've been very busy since last week. I'm working an average of 10 hours a day and when I get home I'm too tired to think of anything but rest. Anyway, when there's some time left for myself I try to dedicate it to watching the Euro2008 football cup either on Spanish TV or on the Internet.
Overtime makes me feel more and more tired each day and by (nearly) the end of the week I'm almost exhausted...
Tonight at 8pm, there'll be an opening party at a friend's store, they've just reopened as a clothes store (nice and cool style) and it's supposed to be a good chance to meet up with people outside work. F will be definitely going but I'm seriously considering the matter. It may be as well a good opportunity to offer my body and mind a good rest at home watching tonight's match or doing whatever facies me the most. Tomorrow I'm not working overtime but on Saturday from 8am to 3pm I'll be al pie del cañón once more, so I'll have to make up my mind...