I've been having some really irregular bleeding since mid-April (of this year). It seems pretty constant, but sometimes there are a few days when I don't bleed at all. I've had this before, from November of 2012 to almost February of 2013, and I did see a doctor who said there was nothing wrong with me. I don't have sex with other people (sometimes I do masturbate but not regularly.) I still have my regular period symptoms sometimes, and they were never every month with the exact same. I've seen my regular doctor for a checkup since and nothing has been out of the ordinary anywhere else, and I've had blood tests, an ultrasound (in January 2013), etc. Nothing is out of the ordinary.
So what is going on?