One tip i might add, When you start running dungeons, state that you are new. 99% of the time you will get people who will be more than happy to help you. That 1% tho can really ruin your experience. So my advice to you is:

Do not let elitist punks get the better of you. They have yet to realize they were once like you. Keep your chin up and take any advice, whether it be supportive or demeaning, and try to better your skills. You will get far in this game if you can do just that.