Hi Guys

I have a bmw 323i e46. A few days ago I started to hear weird sounds under the bonnet especially when I revved up the car and the steering wheel was hard to turn. It turned out to be very low ATF fluid in reservoir. In fact they was no liquid in it at all. So yesterday I topped it up and all seemed to be fine and the noises were gone. I checked the ATF again this morning and it was full but as I was driving out of my yard, the steering wheel became so hard that I could barely turn onto the driveway and soon afterwards the engine switched off. I tried restarting but it only cranks and wont start. Now on the dashboard I have the EML light and the orange triangle light with the circle inside. What could have happened here guys?