5 days after period...Could I be pregnant??

Brianna

I just finished my period last week. I am on the birth control pill. Its been about 5-6 days since it stopped. My husband and I had alot of sex last friday (not trying to conceive) he pulled out. I woke up yesterday and my breasts are sore and swollen. Could it just be my birth control causing this or could I be pregnant that soon with symptoms?