Could I maybe be pregnant?

Okay so I have just hit the placebo pills of my birth control and have been taking them for two days now. I haven't started my period yet but that is normal for me. I usually make it through the four placebo pills before I start. Anyway tonight me and my boyfriend had unprotected sex like we always do and I didn't think anything of it but since I haven't started bleeding or even spotting do you think that there is a chance that I'm pregnant? He came inside of me and all of that. Thanks for your input ladies :)