CTRL key not working properly
If the product you used to clean the keyboard was wet, you could have created a short in the keyboard or perhaps even corroded the contacts under the Control key.

Two outcomes:


You give it a few days to dry out.
You buy a new keyboard.


Hopefully #1 will take care of it for you!

In the past, I've scrubbed nasty, dirty keyboards with a firm brush and water under a bathtub faucet and then let the keyboard dry out for a week. However, that was not the low-profile "laptop like" keyboard that Apple has been providing for the last decade, so I can't say that I've done it on modern Mac keyboards. But that all being said, the key thing is that clean water (NO SOAP!) should leave no residue (unless your water is very hard) and as long as you don't introduce electricity into the mix while it is still wet, you shouldn't be risking creating permanent short circuit damage.