Possible restraining order?

In the beginning, it was perfect, well almost perfect. I thought I had found the one, but boy was I wrong! He started getting angry when I wouldn't text him back fast enough and eventually throughout our whole relationship I felt as though I was walking on eggshells. I tried to break things off with him, but he threatened to commit suicide, so I stayed. Major red flag!! At times, I wouldn't answer his 100 calls, and 71 texts, 91 messages over snapchat, and 34 calls from snapchat (actual numbers) he eventually came to my school, in which he had to be escorted off the premises. He then continued to send threating messages, and even tried to "expose" me without any pictures. I blocked his number, but I'm afraid of what he might do. Should I take legal action, or should I hope it eventually fades away?