If it's not messing with the structure of your course too much, you could create a subfolder menu item for your assessment, split your questions into 1 per page in the subfolder and use Quicknav to hide the previous page and activate Next on completion.

Using css you could hide the subfolder item from your main menu so users can't view all the question pages via submenu.

Another method would be to set up 1 question per article, set a trickle at block level, and use Onscreen settings at article level to display:none on the parent article when 100% in viewport. This means your block will be visible on arrival but the whole article will disappear after trickling to the next.