Sex hurts

It’s been 3 months and I had my fourth child. I only tried to have sex 2 or 3 times with my husband because I’m really not sex driven like I used to be, but I know that at times I should, and want to also for my husband. But every time I’ve tried, it hurts, as if my vagina is ripping apart, like a burning sensation. I don’t get why or when will it get better?