And we have answered a couple of times.
You need to take a pregnancy test.
Symptoms are not reliable indicators of pregnancy, especially when you've also just had a big hormonal change from the pill, which could just as easily be causing the symptoms you have described.
If you have taken your pills are directed and you waited at least one month to be sexually active using only the pill, your chances of pregnancy are very low (and there is no need for withdrawal -- that doesn't work as birth control when not on the pill, and it makes no difference when you are on the pill). If not, then they are higher.
Pregnancy symptoms rarely appear before at least one month of being pregnant, and some women have no real symptoms at all their entire first trimester. Yes, a missed period is often the first symptom, but if you've just started the pill, it can take a few months for the withdrawal bleed to kick in or regulate (women do not menstruate on the combination pill, they have monthly withdrawal bleed -- looks the same, but is different).
So again, want to know if you're pregnant? Take the test. Want to better protect againit and STIs? Use condoms with your pills. This stressed out about pregnancy? Consider not being sexually active right now.
Please don't keep posting the same question -- we're going to keep giving you the same answers because they're the only correct answers to give.
Editor and Founder, Scarleteen
My epitaph should read: "She worked herself into this ground."
-- Kay Bailey Hutchinson