falsely accused of rape and in danger of being railroaded [Massachusetts] : legaladvice

I am a college sophomore at a private university in Boston. I had intercourse with a female from the same university a few weeks ago. I had feelings for her and asked her out the next day and she rejected me very rudely. I told her that I was still open to taking her out with no hurt feelings if she changed her mind. She told me not to contact her again. As a result of poor judgement, a few bad messages and pictures were sent to her. Then a few days later, I get called in by the university police to discuss the intercourse I had with her. I told them that she was retaliating for the messages that I sent. I was just informed that I am being called before a disciplinary council and I am facing sanctions if found guilty for harassment and assault of another student! I am very worried that I am going to be railroaded because they blindly believe this female. I cannot afford a lawyer and I do not want to involve my parents. I am wondering if I can have the case thrown out myself from lack of evidence because thee is nothing to prove that the sex was not conventional. If so, how do I go about protecting myself in such a manner. Thank you.