You could be pregnant. You could be late. I have learned that people can have all the pregnancy symptoms and not be pregnant or have no symptoms and feel exactly like you're about to get your period and actually be pregnant. I don't think it's worth stressing over until you can test and know for sure.
Here are a few tips regarding testing. Only use first morning urine -- it's more concentrated, so it's more likely to give you an accurate reading. First Response Early Response testers are the most accurate at this stage; however, they are pricey, and the ones from Dollar Tree or eBay are almost as accurate. Don't use a digital for early testing -- it requires more hCG than the lines. Also, only use the pink line tests, the blue ones are less accurate.
Do you track your cycles? Not everyone has a 28 day cycle (mine is 33 days). If I didn't track my cycles, I would have started testing for pregnancy 5 days too early, and/or thought I was late when I actually wasn't. If you are trying to conceive, tracking cycles, taking your basal body temperature and/or using ovulation predictor kits (they are cheap on eBay, very pricey in the drugstore) can help!
Good luck!