Why does it hurt so bad!!??

I posted this last night but it was at a really bad time and I need advice bc I’m struggling. So I finally let my man take my virginity. I’ve always had very negative views of sex and my personal sexuality. I felt ashamed and afraid and I always assumed it would be a marriage only thing that I’d just have to do for my future husband. Well that all went down hill in high school. I never trusted guys and this one 20 year old I worked with started flirting and he took advantage of me. Anyways this s something I’ve been trying to work through in therapy but it still consumes me at times. So sex with this current guy and literally everything else we’d done before has been so redeeming. He is kind, respectful, and overall better. He’s also 6”7’ and very well endowed. That’s another problem though bc it’s insanely big. We’ve have sex three times and each time is extremely painful. I think I tore a little the last time. It always gets really bruised. I like it but it’s also so painful. He’s gentle, I’m wet, we do foreplay plenty, and we use lube. My therapist thinks I could have vaginismus bc I have past sexual trauma and anxiety towards sex but idk. I have an appointment with my gyno but I’m still concerned. I trust him so idk why I can’t just relax. I get so tense and I shake but I know I feel safe and I want it. I also have never been able to wear tampons bc it’s too painful which is another vaginismus symptom.