Dose porn define your sexuality ?

I need your opinion and I’m trying to be understanding as much as i can. I saw the porn my boyfriend into, he watches heterosexual porn and shemale and milf. I’m a freak but I’m not that exposed or interested in porn tbh. Because I discovered most of my kinks through my boyfriend and he’s my first. He have a Twitter acc for porn. And it made me feel like our experience is not that sacred. I feel like everytime we gonna have sex I’m gonna think about the things he saw/ into (for example he told me he would like to see me with short hair and i saw one of the shemale he kept retweeting have a short hair cut). I get you watch porn from time to time. But idk about dedicating an account for that. For me to be completely open for everything and into threesome and such is gonna take time. Seeing all that just made me think if we fit. Or the idea that he’ll leave me for something he prefers?

It’s really complicated and idk what’s the right move here. I was mistaken to go through his phone and i have apologized. But he lied to me about not watching porn. isn’t my right to know what’s he’s into?. Idk how to handle this situation. I love him dearly and he dose too. I didn’t hate him for that. But the fact he kept it form me and said before he’s deleting his acc and after that he made a new one.