I think I'm pregnant !!!

On my 5th period day I did not bleed and my boyfriend and I had sex , however on my last day of my period cycle ( 6th period day ) I bled a little .

I was worried about getting pregnant because he pulled out , but I was not sure if he ejaculated and a day after sex, I took a contraceptive .

5 days after my period finished I noticed red to brown blood ... I've been spotting the entire night and I am very worried .

Could I be pregnant ?

please help :(