I was on the 18th day of my cycle and i did stuff with my bf "liquids" mixed but he didn't ejaculate, is there still a chance i could be pregnant?

Yes, there is,,,: There is a possibility of pregnancy especially if there was no contraception, like a pill or a condom. Since you're in your 18th day, there is a chance for fertilization though ovulation is usually a day or two earlier. There also might be sperm in his fluid before ejaculation. So there is a chance even if it's lower than normal. You can do a pregnancy test or see your Dr. for one. Good luck!

Possible: Pregnancy not too likely on day 18 of 28 day cycle and avoiding ejaculation helps but possibility exists. Best to find a reliable birth control method and this time take morning after to be safe.