Kalandra
A week is not long enough to tell if you're pregnant. Like it or not, you'll have to wait for the proper time to take a pregnancy test. Since you claim you cannot go to see a doctor, which I admit... is sort of odd considering your age, you're going to have to patiently wait it out.
I would presume that by your next period, or a week or so before it, you'll be able to tell. You're period is too close right now for it to be based off of anything, so it is pointless to worry about your period this time around.
What you're experiencing right now is a placebo effect. You're worried about being pregnant even admit to staring at yourself while knowing it wouldn't be changing yet, and so you're subconsciously making things change. Our hormones are filtered through our emotions, and being stressed out will alter them. Even cause you to miss a period. I've done it countless times simply through stress factors not even related to pregnancy.
Bottom line: You're going to have to wait. We cannot magically tell you otherwise. Not scientifically possible, especially if you won't go to see a doctor.
I agree with her, I've been in your place right now. I was so worried that my body actually thought that i was pregnant when i really wasnt. it was so awful. There is no way to tell if you are right now. You might have to wait a month or so before you can actually find you. You really should go to a doctor, they would be more helpful then coming on here and asking.