Population growth is in fact slowing down and have been doing so for quite some time. But we'll eventually run into the problem where there won't be enough working age people to take care of the elders.
Many countries (nearly all of the developed countries) are having too few kids to maintain their population and it can only be increased/maintained through immigration. Most experts believe that we will top out at around 10.5 billion in 2100 and then there will be a decline.
Money is created from debt and there will always be more debt than money.