Is There Any Chances Of Getting Pregnant?

my girlfriend and i were having sex the day after her period. we were using a spermacidal condom and it was still really hard because she was extremely dry. when i ejaculated i tried to pull out quick, because the condom broke around the bottom. most of the semen ended up still inside the condom, and a bit around the outside of her vagina. but we dont think very much (if any at all) made it inside. should we be worried that she might be pregnant?