Would I catch HIV off of a gay ex heroin addict?

This is a serious question so don't call me names. I'm new to this gay stuff and I heard that a guy who's been in jail is more liekly to have HIV. He was a heroin addict too. I alreday had sex with him when we was in jail and I cud have it. I dn't know. I asked him if he had it cause of injecting and stuff he said no. Even if I didn't get it from s ex cud I have it from living with him? I lived with him in his house for nearly 3 motnths now