corner broken off of little yellow thing...

[NoNo9]

You broke a piece of a capacitor...
it really depends on how and how much you broke... if it's just a small piece of the cover then you're most likely fine but if it's more than that or if it's disconnected on one of its ends then it's kinda bad news.
It's not fatal though as it's not at all impossible to find replacement smd capacitors but you would have to ask people to tell you which capacitor it is and soldering it back could also be a bit tricky if you don't know what you are doing.