Burnt again

I CAN'T STAND OUR OVEN!! This WAS my oatmeal fudge bars.....our TINY oven either burns things....it's raw in the middle or you have to cook something for way longer than the directions say. Every day seems to be different with no consistency!!Oh and it cooks unevenly....While half the cookie sheet of cookies is burned...the other side is almost burned. The one thing I enjoy is baking and our tiny oven that I can't even fit a regular cookie sheet in is going to be the death of me...I'm sure of it! :) Or at least close to it!