im worried bout if i am pregnat or not

I'm not really sure if your saying you have come on or not, but For future reference, If you are worried about getting pregnant you could always Visit your doctor and get the 48 hour pill, So even if you wouldn't of got pregnant, there's no chance you will be after taking the pill, and then there's other options, like Microgynon (the pill) I was on that for a while, the only issue is It has 3 possible ways of working, it'll either Work completely, and you wont have a period, reducing your chances of getting pregnant, You'll spot (light periods) or it wont work at all, Basically you'll continue your normal period cycle. 

In your case, JUST to be safe, You can either visit your doctor and they'll give you a free pregnancy test, No needles, just a urine sample, And they'll also give you some contraception advice, or buy a pregnancy test from your local store. Even if you believe your not, its always nice to be safe. I made the mistake of ignoring the fact I didn't come on, then a few weeks later my moods changed, and it turned out I was pregnant, and its not a nice experience going through a termination Or going through with having the baby, so if I were you, its best to always check. that way at least you'll have the worry off your chest :) 

Hope this helped