What Causes Altered Sense Of Smell Along With Poor Memory And Nausea?

I m having some abnormal things going on. Not sure if any of these things are related but.... Metallic smell in nose and cough started today Forgetfulness Constantly forgetting to include certain words when typing or writing something, Trouble concentrating Tremor Random nausea Severe back pain (i have chronic back pain, but it s been noticeably worse as of recent) Frequent urination (it s as if liquids are going right through me) not sure if it matters but I m an 18 year old female with no known medical problems aside from scoliosis.