HELP! Ineed Answers !?

alright so i had unprotected sex with my boyfriend on the 21st of this month & it was the first day of my period & a day after that it stopped . then a day after that a brown/pinkish discharge came . am i pregnant ? i know its rare to get pregnant on your period but i had a headache all day , eating Alto , feeling dizzy & nauseated , peeing alot & i'm sleepy 24/7 . this is a bit strange because i know it takes like 2 weeks to show implantion bleeding etc but does anyone knw whats wrong with me ? am i pregnant ? help!