I'm 27 & still confused by my cycle

Shaunte

Please help me understand.

So I had a period back in February 23-27 then March comes around & I had brown spotting discharge (old blood??) From the 10th -16th glow was/is tracking that my period was suppose to start on the 24th of March it never came. I'm on the birth control Nexpolon my 3 year removle date will be this June... so was that brown spotting discharge a period? I'm so confused.