Change is the only constant in life.
Pressure is the only constant at Job.
No matter what you are working as, where you are working, when you are working, pressure is always gonna be there. The question to ask yourself is: Is the pressure making you better? You can't get better if you don't push yourself. When there is pressure, you go outside your comfort zone, it increases your boundaries. Look on the positive side, you are getting better at work because of pressure. Don't think of quitting. Think about what you are capable of and how you can handle the pressure.