What could happen in 24 hours?

Valerie 

"Miss? Miss Valerie?" Sandra's tiny voice sounded in my head. I tried to force my eyes open to tell her I was still somewhere in my body, but my heavy eyelids just won't open. 

"Am I dead?" I asked my subconscious self, but all I heard back was a deafening silence. What happened? Where am I? 

"Miss Valerie, here are the drugs." I felt Sandra gently tap my shoulders, but I still couldn't leave the entrapment my consciousness was in. Unable to make a sound, or see, I knew it was my time. 

The excruciating pain I had felt earlier had claimed my life. But why?  What exactly was it?

I began to regret keeping the illness from my family after my first experience. Like as said, I had a similar occurrence on my 18th birthday, but even until now, I had no idea how it had stimulated such a massive pain that could knock me dead within a few minutes.