Yeah, you definitely have it set on "ideal" miles instead of "rated" miles. None of the Tesla models have 350 rated miles on a full charge. Go into the settings screen and change it to rated, and it will be much closer to your real usage. Ideal is a very pie-in-the-sky overly optimistic type of mileage estimate that almost no one can achieve. Rated is pretty close, but just like with gas car EPA mileage estimates, most people don't drive quite that efficiently, so it's usually just a little bit high as well.
Some Tesla owners recommend changing the display units to "Energy" instead of "Distance", so that it will just show a % for the battery meter, so that it's not in your face that it's a little off, and you won't worry about it. That's a decent thought, but I don't think that way, because the places I drive are not measured in percentages; you always think about them in miles. I don't worry about it; I'm just aware that the rated miles are in the ballpark of being a little high, so if it says 200, that's maybe around 180ish real.
Oh, and if you're accumulating these measurements over several short trips, the numbers are going to be terribly off. When the car has sat for hours with the battery getting cold, the first few minutes/miles of use is going to show insanely high energy usage as it warms up the battery pack, which will level out for longer distances. I have about a 2 mile drive to work. In the winter, that 4 mile round trip sometimes uses up 8-10 rated miles. That's just the way it is for a short trip in the cold with running a lot of heat.