My house has a city-fed plumbing system. Yesterday, the water pressure coming out of our shower elevated to the point that it hurts. I didn't notice a change in how the toilets flush, but a couple of the other faucets in the house seem to have slightly increased pressure as well (I may just be imagining that though). I took the shower head off and cleaned it but that did not help. We bought the house about a year ago and I don't think it has a pressure regulator (where would it be? What does it look like?). Any ideas? What other info do you need?

Get a pressure gauge that fits an outside faucet and check the pressure. The gauge should cost 9 bucks.