2000 Ford Escort zetec 1.6 16v loosing coolant and over heating

And I have to refill the coolant quite alot. I have had to refil the coolant 4 times in the past week. I cant find a leak so I dont know where it is going. Also I have some excess smoke and water comming out. Coolant for the radiator runs out after a couple of days. Heaters stop workiing when run dry. Smoke and water is comming out the exuast. Sometimes the car is quite shakey when first started. Temperature quage goes to red when water is all gone and can go all over the place somtimes. And when driving along with my foot gently on the accellerator it jerks a little bit.