Short term memory loss, clumsiness. what could this be?

For a couple years already my memory has gotten worse and worse. I'm only 21 and i DO NOT take drugs of any kind or drink. People reminisce on things in my teen years that i never remember. Im terrible at telling stories of things that happened even a few hours before. Sometimes i remember my last meal. Many times, i cant remember what i came into a room looking for. I finished high school with great grades and now, i cant remember how to do ANY of the math problems I easily did. This is truly frustrating. A couple months ago it got REALLY bad, i woke up with flu like symptoms and I was extremely clumsy and would stutter or not make any sense in some of my sentences. EVERYTHING i reached out for, i would tip over or drop. That entire week, i was really depressed. Im not sure why i didn't go to the hospital. I am gonna go to the hospital, I missed my appt's a couple times already (because i forgot) but i will go.what could cause this?