If you are basing your assumed range on the "Guess-o-meter" number — Nissan calls it "Distance to Empty" (DTE) — next to your fuel bars, you need to be aware that it can be wildly inaccurate and can't be relied on for range calculations. That number is a calculation based on how you were driving recently. It will vary with speed, weather, heater use, hills, and the like.
A better way to get an idea of range under your driving conditions is to use your SOC meter (% charge) to estimate how much energy you are using. A new LEAF might have about 21.5 kWh usable energy in the battery (but less when the battery is cold). 30% of that would be about 6.5 kWh. If you went eight miles, that works out to about 1.24 miles/kWh, which really is an
exceptionally bad mileage efficiency and suggests a range of about 27 miles. Known mileage killers are heavy heater use, high speed, wind, snow, low tire pressure and, of course, very cold temperatures. Which of these might be factors in your low mileage you'd have to judge.
With practice you can learn to drive more efficiently, if it is a concern to you. I would suggest starting here:
Stoaty's Guide to Energy Efficient Driving of the Leaf
But if you'd like feedback on the range numbers provided by the GoM, sorry, it is known to be nearly useless under varying driving conditions and should just be ignored.