Consider what happens when the user holds down the button - it'll report being pressed every time you test (which can easily be many, many times each second). If you only want to do something on each click, consider using events instead.
Also, as G. said, you need to learn your basic C++ syntax...
Edit: additionally, since 'bullm' can only take on one value at a time, your consecutive 'if's would be more efficient (and logical) as either a 'switch' or a 'if' followed by a number of 'else if's. Or you could simplify by just doing two loops; the first would do '4 - bullm' instances of yellow and the next would do 'bullm' instances of transparent (assuming you cap bullm at 4) - a lot shorter (you'd need to store the objects to operate on in a container (like vector) instead of seperate variables, but that would probably be a good change regardless)...