The first time I worked a set of night shifts on my last one I decided I would just stay up, then go to bed early. BAD idea. By around 11pm I was dead tired, and went to bed so that screwed me up even more. When I was a kid if I'd pull an all nighter I was easily able to do this, but seems I can't anymore. I think the key is what I do on the next day though. Just going on the internet is probably a bad idea. If I did something more active I'd probably have less trouble staying awake.