When you get your hair dyed at a salon, it is done properly and with the appropriate chemicals to provide your hair with nutrients and nourishment, that will allow you to maintain healthy hair, whereas boxed hair dyes contain various volumes of dye, that do not spread evenly throughout your hair.
Thus, I am glad that you went to the hair dressers to get your hair colored.
Don't fret about the intensity of the color. When color is mixed at a hair salon, it is mixed at a volume that is strong or intense. This is because after only a few washes, about 40% of the hair dye will wash out. If a hair dresser dyed your hair 40% less red than he or she did, imagine how much color you would lose. By the time you washed your hair a couple of times, the dye would be almost unnoticeable.
And so, after a few washes (between 4 and 6), 40% of your color will be gone. After that, I suggest using a shampoo and conditioner that will help your color to remain, so that you can maintain the color without it fading. The color in itself, from a salon, should last between 3-5 months, however, to ensure it remains at best quality, try using Joico Color Endure Shampoo and Conditioner, which can be purchased at most hair salons.
Hope this helps!
Own Experience/ Hair and Makeup Expertise