I Have Experienced These Symptoms Twice In 2 Weeks. I

I have experienced these symptoms twice in 2 weeks. I begin to feel tired then my body literally is feels so heavy I don’t want to move hard to lift my arms and it is even difficult for me to talk it takes to much energy. I even feel like my lips are too heavy to open my mouth and my breathing slows way down. My words run together and I am completely drained. I just sit and don’t move and try to relax. What could this be?