I bet you do perfect! I cooked my first "family" Thanksgiving dinner 3 years ago and I was very stressed. All my worrying was for nothing. Everyone came, lots of help at teh end to get it all completed and it all worked out perfectly. There were 19 of us.
Some things I could do ahead of time, but I actually enjoyed getting up a bit early before everyone else and getting the dressing done and the bird in the oven. All teh veggies were fresh. Green beans cooked the night before so they only had to be heated. Desserts were done the day before and heated. Make you plans and your lists and it will all turn out great!