I'm 15. I have only been keeping track of my period for 2 months, both falling on the 8th. I have had frequent sex between thanksgiving and mid December, with protection. it's the 20th and my period still hasn't came. I had period symptoms around the 8th but it never showed. I'm pooping a lot and having heartburn like burps.I also feel like I've gained a lot of weight and I've been having slight discharge. I've also been really snappy and craving my usual period foods. do you think I'm pregnant?