I just got done with my period. it lasted only 3 days. soon after, i started having little brown discharge. is this normal?

Maybe: If your period isn't usually 3 days long, then this would not be normal for you. But you can have normal hormone variations that change your period. If you are sexually active you might consider getting a pregnancy test if it was that much different. If you aren't sexually active, you can wait another month and see how your period is next time.

Not normal: If it isn't what your body (your menstrual pattern) usually does, then : no. But it doesn't sound like anything worrisome, minor hormonal fluctuations, or some 'old' 'leftover' blood may have caused this, and if it continues, or worsens i would recommend seeing your gynecologist for further investigation. **also- always wise to make sure you aren't pregnant..