Oh, they don't mind that, really they don't. That question raises more indignation among Holmes enthusiasts than it does over any other character in... er... fiction. They didn't exist in the strictest sense of the word, although Conan Doyle is said to have been inspired by the acute powers of observation and deduction of one of his medical professors in Edinburgh, Dr. Bell. Watson is undoubtedly in large part himself, and some movie versions have been unjust in portraying Watson as obtuse. He was intelligent but normal.
Conan Doyle was a genuine medical doctor, but not, I think, a very successful one. One or two of his non-Holmes stories (which he preferred writing) deal with young doctors leading a hard life in private practice. He was knighted, not for writing, but for organizing and running a medical unit during the Boer War, of which he wrote an excellent history.
TF Fremantle (great-nephew or thereabouts of the Colonel Fremantle you can see on the field of Gettysburg in the movie) wrote a "Book of the Rifle" in 1901, which includes a list of civilian rifle clubs. "Dr. Conan Doyle" is given as secretary of his club in South London, at a time when his time could have been worth a great deal of money. His was not the usual thriller-writer's knowledge of firearms. Here are three war correspondents who find the freedom of the press threatened in the Sudan:
"This is an excellent revolver of mine if it didn't throw so devilish high. I always aim at a man's toes if I want to stimulate his digestion. O Lord, there's our kettle gone!" With a boom like a dinner-gong a Remington bullet had passed through the kettle, and a cloud of steam hissed up from the fire. A wild shout came from the rocks above.
"The idiots think that they have blown us up. They'll rush us now, as sure as fate; then it will be our turn to lead. Got your revolver, Anerley?"
"I have this double-barrelled fowling-piece."
"Sensible man! It's the best weapon in the world at this sort of rough-and-tumble work. What cartridge?"
"Swan-shot."
"That will do all right. I carry this big bore double-barrelled pistol loaded with slugs. You might as well try to stop one of these fellows with a peashooter as with a service revolver."
"There are ways and means," said Scott. "The Geneva Convention does not hold south of the first cataract. It's easy to make a bullet mushroom by a little manipulation of the tip of it. When I was in the broken square at Tamai——"