I Can't Solve a Simple Equation

Today in math, I took an opener on integral of a function. I did every step right and got down to 6 x 8 + 8. I wrote down 22 as my answer as I added 6+8+8 instead of multiplying 6x8. And Mr. Brose was looking at my opener and told the whole class of my embarrassing mistake. I was embarrassed by my mistake. Its ok though as I will get partial credit on that problem. What a stupid mistake by me!!! I was too I did everything correct but just couldn't read carefully enough.