Check the Power Steering Fluid PSF, it might need to be topped up.
Or steering pump is getting weaker and dying, wait until dies as it takes long time to dye if its weak and its expensive to change.
i bought a Mazda 2 2009 from an agent and i have st recently i have started having problems like sometimes when we lock the door, there is an alarm like sound. this is embarrassing like as if i am trying to break in a car. please help.