in serious need of some advice. 😰😰

Before I start, I know I made like 2 or 3 other posts like this, but I really need advice. I'm going to go into full detail so here it goes. I'm 16 and I'm on birth control (the pill) and I have regular periods that start within a day or 2 of what my period app(s) say, but this month is different. So my LMP starting date was 12/16/16 and my period this month was supposed to start on 1/13/17 and I'm still waiting. Today marks day 9 of my pissed period. I took a pregnancy test and it turned out negative. I'm not experiencing any pregnancy signs/symptoms other than I'm always hungry, I'm having slight mood swings and I think I'm urinating more than usual (but I'm not for sure) someone please help... sorry this was a lot. 😅😬