Grad school fears?!

Has anyone out there ever been in grad school or currently in grad school?  What were your biggest fears or worries? Is there any thing that you would have done differently? Kudos to those that are furthering or have furthered their education. There are infinite possibilities and goals to obtain with having a great education. I am currently in grad school and to be perfectly honest,  I am a little intimidated!  First, I fear that since it is online, I may not be that great with expressing myself. There is also the fear (more doubt) that I may not have time to keep up with assignements.  Please let me know what you think that may help me and others!