How about some basic definitions of cycling terms:
Crank/Crankset: The arms that the pedals are attached to.
Chainrings: The sprockets that are attached to the crankset.
Cassette: On a multi-speed bike, a group of sprockets attached to the rear wheel. The sprockets can easily be removed for replacement. The coasting mechanism (freehub) stays attached to the rear wheel. On modern bikes, usually 8-11 sprockets (speed), but can be 7 speed.
Freewheel: An older type of sprocket cluster attached to the rear wheel. The coasting mechanism is an integral part of the freewheel. Older bikes may have 5 speed freewheels, but most modern bikes have 6 or 7 speed freewheels.
Freehub: The splined center part that the cassette is secured to.
Cadence: The speed you are rotating the cranks. Usually somewhere around 50-100 RPM (revolutions per minute). A high cadence means "spinning" the cranks quickly (100+ RPM). A low cadence would mean "mashing" on the cranks with a significant amount of force, at low RPM (< 60 RPM).
Force applied to the pedals: Again, high or low, often dependent on gearing choices or conditions such as hills.
Dropouts: These are parts of the bike frame where the wheels attach to the bike frame.
Wheel: Unit including Hub, spokes, rim, & tire (although a new wheel might not include the tire).
Chain Skipping: When the pedals surge forward, due to the chain slipping on one of the sprockets, usually on the rear cassette. Heavy wear can cause skipping
Pawls slipping: The ratchet mechanism inside the rear freehub or freewheel use spring loaded pawls to allow coasting. Sometimes these will slip, allowing the pedals to spin without any force being applied to the rear wheel.
Derailleurs: The gear selection devices, one with two jockey wheels giving chain tension and gear selection in the rear, and one with a slot giving gear selection and preventing dropping the chain in the front.
Shifters: The gear selectors that are on your handlebars.
Cable/Cable housing: Connecting shifters to the derailleurs.
Trimming: fine tuning of shifter adjustment.
Chain Stretch: While steel may or may not stretch, as the chain wears, it tends to elongate due to the wear, called stretch. The chain pitch is 1/2". In 12", you should have 24 half links. A 1/16" stretch in 12" is easy to measure with a ruler, and is considered the chain worn out. A stretched chain can accelerate the wear on the cassette/freewheel and the chainrings.
From your description above, it sounds like your cadence is too high (cranks spinning too quickly). As Andrew has said, with the chain physically connecting the rear wheel to the cranks, the ratio of wheel RPM to crankset RPM is fixed by the sprocket gears.
That is unless the chain is skipping, or pawls are slipping (above), in which case, the symptoms will be very different (lack of catching, or lurching of cranks).
If the opposite has happened. Cadence too low, too much force on the pedals, then the issue could simply be shifting, or something rubbing.
Another alternative is that something WAS rubbing, and is not now, and so you are suddenly going faster.