How high is the risk of becoming pregnant?

Hi By mistake, instead of an active tablet, I took a placebo tablet and on that day I had sex with my partner. I should take the active tablet at 21.00 instead of taking a placebo, and at about 1:00 there was intercourse. There was also monthly bleeding, or rather a tip. Since this was the third blister, I used active tablets until the end, threw out placebo tablets and immediately used active tablets from the new packaging. Unfortunately, I did not make up for the forgotten active tablet. How high is the risk of pregnancy? Since then, we have been applying additional protection, but I am worried about the only time, just in the day of skipping the tablet. About 28 hours have passed since the last tablet. The partner did not finish inside, but as you know, this is not necessarily for fertilization. Please reply