Some of my happiest memories are about camping. You'll be with family and have lots of people to help keep an eye on your little one. I say, go for it!
And....as Shane B. said you probably don't need to ship anything ahead. You are camping, not taking home with you. Your baby will need clothes, food, some toys. That's it.
What you have family provide and what you buy on your way to the campground depends greatly on what kind of campground it is. I've seen some very luxurious ones as well as basic, rough it, ones. Many campgrounds can be previewed on the Internet. Oregon has their state parks and campgrounds on the Internet. Check out the campground, take what fits in your luggage, ask family to bring what you think you really need but can't take on the plane. Go and have fun!
You expressed concern about the lack of amenities. Since you're flying in you will have access to amenities before you get to the campground. Two days is not very long. What could you need once you're there?
If you've not been camping I understand feeling anxious. And if you've never been and are the perfectionist sort then I wouldn't recommend it. But if you can roll with the waves and enjoy his family, go and have fun.