not used to not having friends

Hey, in my old school, I was used to having friends or people around me. I had classmates who would wait for me infront of the door to spend time druing our break. I was bullied when I was a child so I'm not talking much to others anymore, trying to make friends or getting attention. I'm now in business school and I understand that people care less, because everyone got their own issues. But I don't really have friends here, I often sit alone in class, because everyone else have a partner to work with or friends. No one waits for me. In the break I often stand next to some classmates and don't really talk much, because I don't want to make the mistake of talking too much and end up being called a weirdo or something. No one really does small talk, it's often me who has to start a conversation. What am I doing wrong?