What could be wrong if your period only lasted two days?
There is nothing "wrong". It is just that your period was light.
Your period is the uterine lining breaking down and bleeding out of
your body. It is possible that your hormone levels were low this
month and the lining didn't really build up, which means that there
was not much blood to come out. If it happens again the next month,
see a doctor as your hormones may need a boost.