The chances are very small that you're pregnant. It's not impossible though because not all women ovulate in the middle of their cycles. You may be a woman who ovulates right before her period.
You can wait another week and take a pregnancy test. It will be a little early for one so if you get a negative wait a few more days. If it's negative again wait until it's time for your period. Either it will come or you will be late. If you're late then test again.
I'm not sure if you know that pregnancy tests can be bought at dollar stores. Even Walmart has them for a dollar or under. I've heard from many women that these are just as good as the more costly ones. I'm telling you this because you may need to buy several and the cost can add up.
We also have a trying to conceive forum here. The women there are very knowledgeable, just like on this forum so you may want to post your question there too for more answers.
Your cycle stays 25 or 30 days monthly? You can get fertile period by subtracting 18 from ur shortest cycle and 10 from your longest .means say ur cycle is sometimes 25days .sometimes after 28 days .so your fertile period is 28-10=18, 25-18=7, that is your chances of getting pregnant are between day 7-18of your cycle.keep attack of ur days for a month.u ll get it.