Cooking too long, or too hot? I have just moved into a new apartment, and am learning the ins and outs of this new oven.  But being new to cooking/baking in general, I find that everything comes out burnt, one way or another.  Cookies, frozen pizzas, etc.

I find that the bottom of everything I put in the oven winds up burnt to a crisp.  The edges wind up overdone and burnt, basically, while the center tends to be slightly undercooked.  I am trying to experiment with the times and temperatures, to get it right.  However, being inexperienced, I am wondering if my oven just cooks hotter than the temperature I'm setting it to.

For instance, my cookie dough says to cook at 350 in a preheated oven for 10-11 minutes.  Cooking to 10 minutes, the center is still undercooked, and the edges are nearly black.  (The bottom tends to be all black)

Aside from the obvious "get a thermometer" response, does this seem to show signs of cooking too long (without preheating long enough), or cooking at too high of a temperature?
It's definitely a sign that the oven is cooking too hot somewhere; the under-done tops and middles are the give-away. I suspect your oven has a malfunctioning thermostat, which is quite common.   Try setting temperatures 50 degrees below suggested, and see if it solves the problems.  Failing this, purchase an oven thermometer to check it.

Another possibility is that there is poor airflow within the oven. In this case, hot air is heating the bottom of the pan, but cannot get around the edges of the pan to heat the top of the baked good.  The solution to this is usually to use a smaller pan, and ensure only one pan at a time is loaded into the oven.  My oven has problems of this nature when I try to bake in both racks with half sheet pans.