What does it mean when you have brown blood coming out of your vagina and it's not your period.?

Depends. It could be your period, but just not what you're used to. It could be intermenstrual spotting. It could indicate an infection as well. See a gyn for evaluation if it lasts for more than a day or two or is recurrent.
A problem. Bleeding not associated with a period should be investigated. You should consult with your physician.