What is critical analysis ?

For my first ever uni essay we get highers marks if we critically analyse the readings.
But these are renowned sociologists, am I really allowed to criticise them or does it mean something else ?

What you are supposed to do is rather the other way around. Construct your own views first having read many views in journals and other sources, then use your sources to support your view. So you cite the sources that support your views rather than apply your opinions to the journals and other sources you have read and that you might disagree with.
Ok, someone will jump in here (hopefully) and disagree with me. So I will add another layer to what I have said:

It is always good to show you are aware of different views and arguments and you do that by referencing them as well. There's a skill that you will develop over time to doing that without criticising them. A published academic has authority but it doesn't mean you can't back up a different viewpoint using another authority.

There are some nuances here that require careful consideration.

Take your thoughts on this from another slightly different perpective, though it should amount to the same thing:

By citing sources across a spectrum of opinions shows you have read widely. A recommended way to think along these lines is to find academics who are leaders in the subject. You really cant go wrong citing such sources even if you are constructing an argument against what they say. Just make sure you are using an equally dominant academic with the alternative point of view you support.

Let me know if that helps at all.