We've had weeks like this. Most recently this past week. It's like he's afraid to miss something, or he just needs to keep on moving. So far though it's never been for more than a week or two at a time. When he does go to sleep, it's for maybe an hour, then he's up and trying to go again. I've always thought that it was because they just mastered something new, or were just ready to master something new, and that his poor little body wouldn't let him quit trying or practicing. I don't know if it's normal, but I know we've been there too! On Monday I had a bookbinding class, left DS with DH, came home at 10 pm, and he was up and playing. Turns out when he went to bed at 7:30 he only slept for an hour, and so it acted like a nap. I finally took him to bed with me at midnight, and I feel asleep before he did! Normally, though, it's more like your little guy--screaming, fighting sleep etc. Monday was an exception, because DH let him get up, so he decided he'd just had a nap, not bedtime!
Hang in there!