All my writing in iBooks got deleted and there is no way to recover it 😡

I’m preparing for a college essay and I used a pdf in iBooks on my iPad so I can write out my plan for my essay. After 2 hours of gathering quotes and mapping out what I wanted to say and was finally gonna start typing. All of my writing disappeared when I hit the 3 lines on the left because I wanted to see the full page. I’m extremely irritated and frustrated because I spent so much time preparing to type out my essay only to be set back by this. Does anyone know how to recover all my hard work or am I just out of luck ?