Yesterday I Felt Faint And Slightly Dizzy, Iwas Sweating, It

Yesterday I felt faint and slightly dizzy, Iwas sweating, it seemed like my pulse was rapid, my hands were shaking, I felt weak - slumped in a chair. My husband brought me some water and some food after 20 minutes or so I felt better but went right to bed and slept from 12:30 to 4:30 pm. I have lots of medical issues including anxiety. What could have happened? I'm 59 with liver disease.