There are two kinds of inflation - commodity price inflation and hyperinflation.
The United States will not experience consumer price hyperinflation because the Fed is trying to feed the new money through the banks, but there is a credit crunch.
What the United States is experiencing is a commodity price inflation. These can go rather high - as much as 300-600% up over the course of a commodity price cycle - but that is not a true hyperinflation.
And if the commodities going up are as basic as gas and food, that can very much be felt. Most people notice major increases in food prices pretty quickly and also react to them rather definitively. And increases in gas prices can propagate rather thoroughly throughout the entire price structure, and rather quickly at that.
But what is going on in America in current times, with the rising prices in some areas of the economy, which many people fear is going to turn into a hyperinflation because of "all the money-pumping" by the Fed, is in fact a commodity price inflation. Those prices can go up a lot - most people would not regard 50%-100%-200% (which has already happened in some cases) as a small increase - but that is not a true hyperinflation. Most people would also react to increases of 50%-100%-200% by cutting way back - but it is not a true hyperinflation.
The commodity price inflation will probably go high enough to cause a real problem - but it is not the Fed's "money-pumping" (which is not getting into the economy anyway because of the credit crunch) that is causing the problem, it is the increases in prices of commodities that are due to increased world-wide demand and/ or weather developments around the world that are reducing supply and therefore causing shortages (depending on which commodity one is talking about).
I am certain that the increases in prices will cause problems - and I am also certain that the reduction in consumption that will result from the increases in prices will help bring on the deflationary depression that I am predicting (when demand for a product goes down, the price will come back down, as well) - but the increases in prices are not hyperinflation.
Although the Fed is trying to pump money into the economy to stave off deflation and boost the economy - and that attempt has made the Wall Street traders excited and they have therefore bid up the stock market - the money is not actually making it into the economy (at least not much of the money) because of the credit crunch, and so the economy is not really being boosted and, in fact, the money is therefore not having much of an effect on the economy at all. (What is actually happening is that a lot of the banks, maybe even most of them, actually probably most of them, are investing money in Treasury securities instead - because the banks now regard that as a safer return than lending out to individuals and businesses, many of whom are now regarded as a higher credit risk, on average. In other words, the banks are using the money to help fund Obama's huge deficits.)