My pilot light keeps going out

Does it go out after every start up?does it get blown out when the blower comes on? Could be just a simple thermocouple needs replacing. Could be the bulb on end of thermocouple has slipped down and is not in the flame of the pilot, could be much worse, lets don`t think about what could be worse till you`ve checked out the 2 could B`s

It would work for several days but now it goes out after it reaches temperature.