I Feel Really Weak Then Sleepy I Am Aware But

I feel really weak then sleepy I am aware but feel like I am sinking into the floor and feel cold. Then after probably at least a hour and a half I try to force myself to wake up my heart beats really fast like I'm on a fast ride or a train I can hear and feel my heart thumping my ears pop my palms on hands feet feel like hot steam is coming out my I feel thirsty my head hurts my back hurts from behind my heart I feel really tired like I have done a workout I have no energy