Back pain!

Today I scaled all 4 quads on my little brother Ben. It was craziness! I was worried that I wouldn't finish in time. He had a TON of calculus on his lower lingual anteriors and he has a lingual bar so I ended up using the ultrasonic to help me to get off all of it. I have a really hard time scaling the upper quadrants. I think it is because I have to use indirect vision a lot and it really confuses me. My back is killing me so my posture must have been not so hot.... or my muscles aren't used to it. I'm not sure which one. I only missed 3 spots of calculus today. 2 supra and 1 sub. I feel pretty good about it! I'm exhausted!