so long as the supply of goods and services rises proportionally to the increase in money supply, the price of money remains the same. and that is exactly what is happening now.
Goods and services are not rising proportionately with the increase in money supply. The money that's been printed is simply not reaching the real economy. When money is printed it is given to the banks with the aim that they lend to businesses/consumers, but the problem is people don't have the economic confidence to expand or start up new businesses given the current climate, so it is hard to actually get them to borrow the money. This coupled with the fact that the criteria for borrowing money is now stricter since a lot of the blame for the banking crash was put on banks for making bad loans, this makes it even more difficult for the new money to reach the real economy.
You said in an earlier post that printing money devalues the currency and causes inflation, which is correct(in theory) but that is actually the aim.
Money is being printed because the long term fear is deflation not inflation, and the current lack of demand is squeezing down the profits (or forcing out of business) those that supply goods and services. The whole point of increasing the money supply is to make it less valuable so that people start parting with it again and demand for goods and services goes back up and decent growth is restored. Whether that actually happens or not is a different matter.
Japan has been in a similar situation with deflationary pressure and stagnant growth since the 90s, they have undertaken several rounds of quantitative easing along with other measures of fiscal stimulus and rather than this causing an inflationary spiral, inflation there is still deadlining.