intense bleeding after sex?

yesterday, i had sex with a new partner. i've had sex wth 2 other guys prior. The guy i slept with this time is HUGE. and i mean like really huge. and my vagina is not very big. He pulled out at one point and i was bleeding a LOT. he hit my cervix a lot and it was painful but over never bled like that before during sex. i was so embarrassed, but is there any way to prevent it from happening, or any explanation of what it is? i'm still slightly spotting today.