I'm doing some online courses over the holidays since I'm way behind in all my work at uni.
Admittedly the holidays are a bit of a distraction and this is a course (cross faculty sort of thing) that is supposed to be more 'lightweight'. But I read trhough my stuff and I just FREAKED the other day when I discovered that I had missed a quiz which was worth 15 percent of the course which id already studied for and all geared up to take. And students who didn't take it before would not be allowed to take it again, I was told.
Thank goodness a lot of the students taking the course are int'l students and many had difficulties logging on in Asia due to the earthquakes... so the quiz had to be extended in the end.
But I'm terrified I've missed out other vital info. I mean I read through the profile and everything and online courses just confuse me because lets say your instructor writes in huge bold red letters "be sure to check the __ page regularly", but you didn't see the page that was written on to begin with. I mean, the info is everywhere! I checked the course outline and all that but somehow got confused and missed that bit. Arrrrrrrr!

e-mail your professor a.s.a.p. and let she/he know what is going on.

I've taken many online courses and they are serious and right up there with in-class courses as far as work load and deadlines. This keeps them legit in the academic world.