Am I pregnant?

Ok, so I haven't had my period in two months, and my boobs have been really sore for about a month now and recently started to really hurt to the point where I don't even want to lay on my stomach at night. I wake up feeling sick, but I never throw up and the feeling goes away after a few hours. I've been having some lower back pain for about a week and every now and then I'll get a headache. I'm no sure if all this is because of stress or what, but I really need to know what y'all think!