What are the chances of pregnancy if condoms were used but he didn't pull out?

No Leakage, no worry: If the condom functioned as it was supposed to, there is no worry. If any semen entered your vagina that is a different story, but as stated, you should be fine.

Possible: If condoms are used perfectly, the chances of pregnancy are low, but condoms sometimes break, fall off, or are put on too late. So condoms are not 100% effective in preventing pregnancy