Could I be pregnant

Before I had sex I checked my <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">period tracker</a> and it says the risk of pregnancy is low about 3%. We did not use a condom but he always pull out in time. I do take combination pills everyday. Is there any chance that I’ll get pregnant? Should I take Plan B even though I do take my combination birth control pills daily?