I think the exclamation mark is the tyre pressure. Pump up all the tyres and press the button under the handbrake and keep it pressed until the light goes to yellow. Drive at a constant speed until the light goes out.
The mini handbook i have here tells me there is a problem with the airbag if the light comes on goes off briefly and then comes back on.
Take it to a dealer and get it checked as it could result in the airbags not operating if involved in an accident.
HTH
Ryan | 
