If i play sports a lot does that make periods take longer to come because i still didn't get my first period yet. should i stop sports?

Yes: Your first period can be delayed if you're very active with sports. Nevertheless, you should still have other signs of puberty. I recommend any young woman beyond age 15 that has not had a period be evaluated. You do not need to stop sports, but if your examination and labs are normal, you I would probably give you hormonal supplements to make sure you're not losing too much bone denisty.