Could I be pregnat? I had unprotected sex 8 times in a month. Theni was late on my period. Got it the next month for only 2 dayz n it was dark brown. I've tookin pregnacy test they all came out negative.

Pregnancy . Pregnancy is highly unlikely. To rule it out a blood test could be done. Your menstrual irregularity suggests anovulation. Are your periods always irregular or just this month?
HPT. Agree with Dr. Musinski. Did you take the pregnancy test right after it was late or have you taken one at least a week later? Blood pregnancy test is the gold standard.