I had sex toward the end of my period. If he didn’t cum in me can I still get pregnant?

Technically, yes, though the chances are very small. The 5 days leading up to ovulation and the 24 hours after ovulation are the times of highest risk for pregnancy. If you ovulate close to the end of your period, you might be in that window (though it’s unlikely; most folks are around 7-10 days later). The other risk is pre-ejaculate. Even if he didn’t cum inside of you, pre-ejaculate often contains small amounts of sperm which can live in the vagina/uterus for 3-5 days, waiting for an egg. However, I would say your risk is very low.