Okay, my story is a bit different, but I've been in the CC terror boat, so here goes:
I was on the pill, and I had been for a year. It made me quit having my periods, which is a typical result of that certain type of pill, so that was no big deal. That was until a few months ago when I suddenly started getting "periods" again. They were spaced about 2 weeks apart, and I got them continually. I say "periods" because I'm not sure what was my actual cycle, what was breakthrough, what anything was. It was just so sporadic. I also would get on and off weird discharge. I didn't do anything about because like said, it was on and off, not constant. Eventually I decided to go ahead and call my GYN because I was due for my annual anyways. Upon calling, I was told that last year my pap had come back abnormal and LSIL and that they had tried contacting me about it (WHAAAAT??? Also why did they never try calling???). So this freaked me out. Instantly all of the bleeding and discharge (and lower back pains as well) added up in my mind and I was sure it was CC. I was mortified. I couldn't eat or sleep.
So I went to my appointment. The doctor was super calm about it. Said the bleeding was probably just that my body wasn't responding as well to the hormone level of the birth control and the bleeding was that. He did my pap and sent me on my way. The next day, I had spotting. Normal after a pap, I know, but it cleared up and the next day I started getting heavy bleeding. I freaked out. I called the nurse, and she said because I was stressed out it was probably just that my period had come early especially since it was so irregular anyways. I went with that, but after a few days, I got really bizzare-o discharge, flipped my lid, ran to the ER. ER doctor told me that everything was due to a triply whammy: yeast infection, BV, and UTI. Don't know how my GYN missed that just a week earlier, but apparently I caused it through stress - which can make all of that go crazy.
I took all of my meds as prescribed and the wonky bleeding and discharge halted. At least I thought. A few days after I quit taking the meds, spotting again that got heavier and heavier. I flipped once again, still thinking it was surely CC, and ran to the ER. The doc said that the bleeding seemed to just be menstrual and attributed it to the BC just like my GYN, he said that the infection wasn't all the way gone and they needed to do a wider spread of antibiotics. They also did an ultrasound which didn't turn up anything.
So I left with my antibiotics and went back home to lie in bed and dread that they still missed something. I got a call from my GYN to let me know that my last PAP had come back as normal so no further action was necessary. I quit taking the BC and the bleeding has stopped. I have a followup on Wednesday to make sure that everything is totally good to go.
But yeah, so my situation was a bit different, but I know that fear. I don't have insurance either, and I know how frustrating that can be.
I can tell you that I've heard plenty of times, from my GYN included, that as we get older our bodies change and that can cause our cycles to go wonky. Tons of things can: stress, diet, weight change, etc.