I'm 17 have a boy friend who I have sex with some times unprotected today is my 2 day of my period and I'm hardly spotting which would normally be heavy.can I be pregnant

If you have sex, especially unprotected sex, than pregnancy will be a possibility. For most women a missed period is the first sign of pregnancy. For others, they will notice an unusual "period"... often lighter in flow and/or lasting fewer days than their norm.

See if it is just an off period... sometimes they aren't always the same. If it continues to be very different from what you are used to, try a pregnancy test.