I was really nervous the first time I flew, but after taking off, it honestly just felt like a bus or car ride. You don't even notice anything. I'm not sure nowadays what they serve you on flights (I know they cut back a ton on food) but they sometimes give you pretzels, which are nice. They usually let you bring food on too, sometimes I'll order a salad or something for the whole flight (I fly to Cali too usually every summer from Detroit). Since you can only listen/play with electronics after you take off and before you land, I always bring a book so that I can concentrate on reading.
About the brown bags - usually in the pocket of your seat they provide 'bags.' Also, if you're super nervous take a little bit of Dramamine. I have YET to see any motion sickness stuff at Detroit Metro (wtf, lots of people need meds for flying), so maybe get some before you take off.
Candy might be good too, I've found that hard candies calm me down a lot, like peppermint things.

Good luck though! I hope you sit next to some cool cat instead of lame family members - I once sat next to this lady for Ireland and we talked the entire way! It really took my mind off everything.