And another rough night

Man, I am so tired. Last night the boys alternated waking up, so that I never got more than about an hour and a half of sleep at a time. I made the mistake of closing the bedroom window when I went to bed (11:20ish, later than usual). It was an attempt to keep Noel from getting cold during the night, but it just woke him up, so I had to feed him to get him to sleep again. Then Dom woke up around 1:30, screaming. He told Mike that the light was coming down, but it would stop if it were turned on low. He went back to sleep completely hidden by the covers. Noel woke at 3:00. Dom woke a second time (4:00ish?), screaming again, and Mike finally got him back to sleep on the couch around 5:30. Noel was up for good by 6:00, Dom by about 6:30. What's going on with these boys? If anyone has any advice for dealing with nightmares in three-year-olds, please share!