The pills I took I got them in June 2010, but that was my last taking them cause I wasn't sexual active on till now 2012 when I went on my vocation with my new boyfriend,but I was taking those pills that I got in 2010 didn't know birth control have expire date but I spend 1 week on that trip and we have sex everyday but as soon as I come back I see my period but it wasn't the same color it use to be.. so now I'm wondering if I might be pregnant

You aren't protected right away when using birth control pills, and you also wouldn't notice signs of pregnancy just several days afterwards. Yes, you could become pregnant from the sex on your vacation. However, the unusual bleeding might very well be due to starting the pills again.

You will now have to wait and see what happens when you would normally expect your next period. Of course it would be a good idea to speak to your doctor about updating your prescription as well.