Sex hurts?

So I've had sex with my SO many times before and have always used condoms. So after a pregnancy scare we stopped for awhile and my period became irregular so we waited for me to have another then when it was over we said screw it and had sex again. I was so turned on and was craving him when we did it. Now I'm a big girl but I'm really "tight" (sorry tmi) down there and he is really big, but it's never hurt before besides a little uncomfortableness on the first time. Now this time it hurt so bad and I bled a little even though we used lube and I was super turned on, why did this happen? Why did it never happen any other time?