What is going on in my head?

I feel so confused about my life.  I seem to be watching as the world go by.  I feel stuck.  Work is fine, school is fine and almost over,  socially everythings great, even perfect.  I have nothing to complain about, but yet I feel so empty and unfufilled.  I don't know whats wrong or why I feel this way.  I love my life and everyone in it.  I am not mad at anyone.  I love my friends and family and I am very grateful for them.  I can't imagine my life without them.  But again why do I feel this way?  What do I do?  Ugh!!!!