Worried...

Ha
Hey guys I haven't gotten my period since October. It happened back in summer but came again regularly for about 2/3 months until October. I fear that I might have PCOS. I've had an ovarian cyst before at the age of 18/19 cos I didn't get my period from December all the way to March of 2015. The OB/GYN I went to prescribed me a 10 day pill to get my period then I was to take birth control. I came back 2 months later and my cysts was gone. Now, November of 2015 I stopped taking birth control and I've been regular since then until June 2016 came and I was 2 months late then it was regular again from Aug-October. Now, I haven't gotten my period yet. My sister was revently diagnosed with PCOS. She was missing period and was gaining a lot of weight and same as I. I haven't made an apt to my gynecologist yet but I will soon. I'm just scared they might tell me something like I have PCOS or something like that. I try to be positive and just think maybe bc I've been stressed but now knowing that PCOS runs in our family makes me scared. At the moment, I'm not really TTC but I'd like to in a few years maybe in the next 4-5 years but I'm scared of why I'm irregular. Any advice guys??