Russells review: Sealy posterous bed

We bought a Sealy Posturepedic full-size bed (about R4999 on sale from Russels) a few weeks ago. A couple of days ago, we started hearing squeaking noises of mattress springs.
There is loud squeaking when we get on the bed, but we hear the squeaking even when we turn in bed. And it's getting worse. When we make our bed and our knees lean against the mattress side, the "spring sound" is very loud as well.
There is no depression issue that we can see. Is the squeaky noise normal after a few days's use or is it a problem with our mattress? Please help