Welcome!

Those little white bumps on the hair strand are spots of damage on the strand.  I've found that I get these if I have mistreated my hair (coming or brushing while wet, tried to detangle too quickly, using a bad hair toy).

I'd suggest checking out the section on this board that explains a few things about growing long hair.  http://www.longlocks.com/how-to-grow-long-hair.htm
I'd particularly take care with how you treat your hair when it is wet/damp. 

How long is your hair now?  Is it curly, straight?  Do you wear it in a ponytail, or loose?  Tell us more!  We'd love to hear more about your hair.