Could i be pregnant or do i just have a wierd period?

Ok i want to know what is exactly goin on with my body.On the 2nd and 16th of june i had with my boyfriend sadly without protection.I started my period on May 28 i started my period and ended the 1st of June.I should be startin my period on the 27 or 28 of this mont but for some reason i started on the 22 wed. my period was very heavy and normal,but yesterday it got very light.Today i baraly had any thing it was very light pinkish.My period usually last about 5 days so this is very strange to me.I want to know if im pregnant.Im 16 by the way,and i understand i shouldt have at this age yet,and ill make sure this is not goin to happen again.Please help cause i need to know.i havent takein a pregnacy test yet because im not sure if that was my period or not.Please help and thank you.