Lump in upper right quadrant, what is it?

My mom has a knot on her right upper quadrant, right below her rids. Well that's the side where the liver is located. We going to the doctor in a few but I'm praying it's not what I think. But what can it actually be. Because lumps and knots are not a good sign. My mom didn't fall or anything but I'm just worried. I love my mommy