It's possible the weight loss affected your hormones. Fat is biologically active and your fat cells secrete hormones. Therefore loosing weight can throw off your hormones. Especially if you lost it rapidly.
I would recomment seeing an endocrinologist to give you a real diagnosis and to give you bloodwork and hence a more accurate assesment of what hormones are out of whack.
I knew I had this disorder for years before I saw someone qualified to help me. I found out I was also hypothyroid in addition to PCOS. This stunted my weight loss greatly and made me wish I'd gone on tyhroid meds sooner. Also I have crappy insurance and it covered an endocrinologist vist.
hope that helps