Battery fully charged but mileage reads around 85

I bought my leaf about 3 weeks ago. When i bought from the dealer it was showing 100 miles fully charged. Once I got it home I only had a 16v plug and charger to use for charging. It started showing only 94 miles with a full charge. I had an electrician install a 34v plug for me with a 50v circuit. (I hope this is making sense. ) Ever since I started using the fast charger the mileage shows only around 85 miles when fully charged. And i noticed that the double rings around the regenerative braking indicator are reduced to single single rings until the car has been driven for awhile. While the mileage indicator in reduced, it also doesnt mark the miles driven properly. Ex: I will drive 10 miles to work, but it only take 3 miles off the indicator. Then on the way home later it will loose maybe 2 or 3 more miles and then start regenerating and the miles will actually go back up while I am driving. So a total 20 miles trip is only showing a 5 mile depletion. I am worried that the fast charger I got could be overheating the battery or messing up the mileage somehow.

First, don't worry - your Leaf is likely fine. The range estimate is based on most recent driving, so it changes with a new driver. It is also VERY inaccurate for many drivers, which is why we refer to it as the "Guess O Meter." Your Leaf should have a State of Charge (SOC) display option, and that is your best bet for knowing available range. If you have an SV or SL you also have a more accurate range estimator available in the Navigation system.

Now, about terms: I assume that when you write "v" you mean Amps, or "A", rather than "volts". Going from a 16 amp charging cable or station to a 34 Amp unit won't harm the car - the onboard charger is limited to, at most, 27.5 amps regardless of how much a charging station "offers" it. This is much less than a Quick Charge station provides, so heating isn't a problem. (What you have is a Level 2 or "L-2" charging station.)

Just wait until you mountain drive! The GOM might read 20 miles when arriving at the trailhead, and then 60 miles on the way back down.

The car minimizes the amount of possible regeneration (indicated by the single bubbles) as the charge level approaches 100% (and at low temperatures). This is normal. I don't like the driving feeling when fully charged--it feels like the car is running away!

Hope you enjoy the LEAF!

Range drops in the winter. Part of it is the physical effect on the battery, part of it is the condition of the roads and a lot of it is how much cabin heating you use.
I routinely see my range "increase" during my first drive of the day in the winter as the battery warms up. It is not real, in the sense that the displayed range first thing in the morning is artefactually depressed from the cold battery temperature.