Is it OK if will have my depo shot this month? I had my last shot last December 2012.. I need your response.. thank you

You should have had it in March. Why would you think it's not okay?

I missed my shot last Marchand until now.. is it still advisable to do the shot this month? Might there be a problem I encounter about this?

If you are sexually active you can expect pregnancy. There is no form of birth control that is 100% effective.