My partner and I had sex last night and the condom broke, he pulled out immediately, and there was no cum in the condom - we think there was a slight chance there may have been precum though. Because of this, I took a plan b immediately. <a href="https://play.google.com/store/apps/details?id=com.glow.android.eve">Eve</a> and other ovulation calculators say I should be ovulating today although it's known that these aren't always 100% accurate. What's the chance that I could fall pregnant?