Unprotected sex, pregnant?

Before I begin I just want to say, I don't want people telling me I'm stupid or childish, this was a total mistake and I didn't mean it.

Basically me and my boyfriend are both 18 been together 3 years, tonight things were getting heated up and to cut a long story short he put his dick near me to put it in with no condom on and I said go on I dare you, thinking he wouldn't do it, but he did, it was inside me for about 15 seconds not even that much maybe, I will admit there was precum because I felt it on the end of his dick before he put it in, according to my app on my ipad I'm due to ovulate tomorrow, but apparently I'm fertile at the minute. We always use a condom but neither of us had one with us, I'm not on the pill either

What's the chances that I could be pregnant?

**no rude comments or answers please**

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