Could i be pregnant?

Okay so I am 16 and my boyfriend and I are sexually active. My period is a couple days late but we have always used a condom and it has never broken. But I have also gained a decent amount of weight and it is fat and I read online that gaining weight can mess w your period. I also have all the symptoms of ny period starting, like bloating cramps headaches and moodyness. I have always been kind of regular except for a couple of periods they would be 2-4 days late and even one time 8 days but i wasnt having sex back then so I didnt think anything of it.  So now I am freaking out. Someone tell me I am being a hypochondriac.