Yeah it's too early to test. You may just be having PMS symptoms right now. You have to wait until you are due for your period to test. They do have tests that say you can test 6 days sooner but I tested negative on one at 6 days before my period and then at 4 days before my missed period I got my positive. But that being said if you decide to do a test that is done early and is negative I would make sure to retest again if your period is late. The reason you have to wait is because it takes time for the baby to implant itself into your uterus and then it starts to secrete HCG and it takes a few days for your levels to rise to a detectable level. If you are a week late for your period then test again and if it's negative call your doctor to see if he wants to do a blood test. Use your first morning urine for the most accurate results. Good luck.
If it was a week ago and your finished your period last week also then you could definitely become pregnant if you ovulated early. I would say wait at least 14 days after the last day of unprotected sex and then take a home test. If it shows negative then wait until your period is due and take another test =) Good luck!
It's probably too early to test. It would be best to wait and see if your period shows or not!