Expanding on @Mayer's answer, there's a valid chance that it's a swollen battery, or a faulty Trackpad.
CoconutBattery 3.3 is the current version, and it's a good tool for assessing battery problems.
http://www.coconut-flavour.com/coconutba...
iFixit's Guide to 2014 Retina Battery Removal:
MacBook Pro 13" Retina Display Mid 2014 Battery Replacement
First, use that program and see if "Service battery" or anything other than Good is listed. Design Capacity should be high, too.
Second, as a diagnostic, open your retina and loosen the battery screws as much as you can, relieving any pressure from a swollen battery, and see if the trackpad gains some sanity. If it does, time for a new battery. If it doesn't, it's a trackpad.
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