Implanon

I'm on the implanon birth control. It's my second round of it, so all in all I've been on it almost 5 years. I have exactly one year left and I actually just had my first real period since I had the first round of it. So almost 5 years now and no real periods. Just some light spotting here and there, before I got my period, my boobs were killing me which is not something I am used to at all and then I got my period a week or so later. Was I ovulating and do you think my birth control is wearing off?