At the moment it must seem overwhelming, the thought of 10 people in your house to eat dinner! Well, as others have said, relax
. Turkey isn't difficult and there is definitely that 20-30 minute let it sit time to deal with finishing things off in the oven. If you're making mashed potatoes and aren't comfortable making gravy there's no shame in using the canned stuff. No one needs to know and probably no one will care. I take it you wouldn't invite people who would be critical of it, would you? Uh, let me rephrase that, considering family members are often the most critical... you wouldn't invite anyone whose criticism would actually hurt your feelings... uh, let me rephrase that...
You'll be fine! Just make as much ahead of time as you can and relax and enjoy the day and the food!