I would say no, ive had an escort gti in the past which did the same thing, it gradually got worse i.e if i changed gear at 4k rpm the revs would stick there when i pressed the clutch, i had to get the idle speed sensor changed(or throttle position i forget now).

Definitely shouldnt stick that high, it should drop down to 1 or below like any car.

Id get it sorted as soon as you can, it may get worse and it'll be reving its nuts off every gear change