What Causes Pain In Head, Pressure In Chest And Fainting?

It's been two days since I've been having a very sharp pain in my head, my heart will accelerate all of the sudden, sometimes I can barely breathe, there's a lot of pressure on my chest, if someone asks me a question they have to repeat it at least three times for me to be able to answer it, I fainted two times yesterday, and I also have drowsiness.