Am I pregnant or not?

Me and my boyfriend had unprotected sex last week on Sunday an I was on birth control but I havn't taken it since last Saturday, an then on Monday I got my period an it was lighter then normally, an I didn't know if I could be pregnant or not. What do you think?

It is possible.
You might have still been protected and the sperm could have died. But if there was sperm still alive and you ovulated then it is very possible. It could have gone any way really.
Get a pregnancy test to be sure.

Yes it is possible, only have unprotected sex while on birth control.....but keep taking birth control when you are supposed to...you are supposed to take it once a day at the same time each day and if you skip tablets you are not covered for pregnancy so it is possible.