Input on a possible sprained knee?

I twisted my knee at work. I am jumping through all the hoops butthe doc my work sent me to spoke extremely poor English and I have no faith in her medical opion and am scared she may have mis diagnosed, she never showed or explained to me the results of the xrays she just said I have mild sprain and said I could go back to work the next day. Ever since the injury my knee pop really loud and hurts horribly every time it pops I can hobble on it but it gets real uncomfortable real quick, it not too swollen but it's the crunching when I bend it a lil and the constant, painful, popping when I hobble and move it that has me worried. Any thoughts or experience with this type of injury?