Period Question

Hi Everyone.

I am 15, I'll be 16 in less than a month. And I haven't had my first period...

I seem to be on my way to getting it, I've had discharge (egg white like) since 20th January 2021 (I like to keep track of things) and I had breast buds come in for the first time September 2021.

I am a little worried about pcos, my half-sister (we share the same mum) got her first period at 16 and was diagnosed with it. She's 26 and gets periods every 3 months or so that are heavy and painful. We've talked about it a little but not into great detail. I asked if it was genetic, and she said yes but our mum and grandma didn't have it (they've both passed away). I can't vouch for any Great Grandmothers or anything.

I have a plan, if it gets to March 2023 and I am still not menstruating, then I will got to a doctor as I will have had discharge for over a year, and it will be the year I turn 17. I can get checked for pcos then.

I'm not looking for anyone to tell me to be grateful I'm not bleeding out of my vagina every month because I'm past that, I want to be normal.

What I'm looking for is stories from people who got their first period as late as 16 and/or stories from people with pcos so I can learn more about it. I just want to relate to someone and to feel normal. Thanks :)

Edit: Just some extra info, I don't do any sports. Nothing to delay my period. I am 4'11' (shortest in my year) and weigh 6 stone. I eat very healthy with and aunt who home cooks' meals with at least 5 vegetables in every night, my diet is varied with everything a normal teenager needs: pasta, white meat, red meat, greens and a few treats (I'm not vegan or vegetarian or anything). I did have a blood condition about a year ago. It was ITP, which in a nutshell meant my blood was 'runny' (I lacked platelets) and wouldn't clot - so if I got a cut/nosebleed it wouldn't stop bleeding. But one of the symptoms was heavy periods not delayed periods and the doctors say other than that, the condition wouldn't affect my menstrual cycle (or lack of it)

Another thing, when writing this I got a sharp pain in my stomach. Alot lower than normal and I've not had that before. It lasted half a second and that was it. What to period cramps feel like? How will I know? I have so many questions and I get frustrated knowing I'm the only one out of my friends going through this. All I want to do is talk about it to them but after a while they brush me off with a "You'll understand when you're older" which I hate because I'm the oldest out of all of them and it's so patronizing and makes me feel so much younger than I am. It's shit.