Okie, well, you can be pregg, and bleed. Its not called a period when you are pregnant and bleeding, because a period is caused in your monthly cycle, (when your uterine lining sheds and the egg dies, etc)
my mother, had a similar occurence happen, she bled for two days and thought it was her period, later, she found out she was pregnant with my sister.
I suggest a test, if it is negative, but you still think you might be pregnant,there are other alternatives. A blood test from the doctor, perhaps, or, you can ask for an ultrasound to be sure. (sometimes pregnancy tests dont read out like they should, but this is very rare) also, women with abnormal periods have a hard time tracking a pregnancy, I have known myself to go for three or four months without a period, and still not be pregnant.