Please give your game a name, even if it's a terrible name, and please also give the girl a name because just calling her "the girl" and having, basically, no story context makes her a fetch object and that's dehumanising.
I got to the point where I was supposed to find a lighthouse and I found five lighthouses but couldn't get to the fourth one, no matter how I tried, and none of the others had a note. I eventually realised that at some point I must have moved through a hole in the scenery that wasn't plugged and was now running around in the scenery area and outside the game area. After about half an hour of running around hitting barrier after barrier (visible and invisible), trying to figure out where the gap was and how I got there, I eventually gave up.
I only saw one zombie right in the beginning out a window and then later a few way off in the distance past a body of water and barriers I knew I couldn't/wasn't supposed to cross. I didn't have to go into the maze because I found the note outside the maze. So there ended up being no scare factor and no danger.
I presume your main task was that you programmed the game, so my only other major comment is that the mouse control was way too sensitive. When I first started playing I was upside down half the time. I eventually adjusted my hand movements to compensate but it wasn't comfortable. I don't know what else you might have done (I'm presuming not the art) so I can't comment or offer any other feedback.