Ford Mondeo mk4 - Airbag light illuminated on mk mondeo - buster1971

I have a mk 4 mondeo titanuim x and a few days a ago the aibag light come on when i went over a speed bump,this have just been a coincidence though,i had only owned the car for a couple of days when this happened,the following day the light come on again after 10 mins of driving,the light is now illuminated all the time,is there anything i can check myself or is this a job for the garage?