I'm going to Chicago soon and I'm looking for a backpack that will fit all of my needs. I'm going to be there for an extended weekend so I want to be able to bring several days worth of clothes with me on the way to there. Once I'm there, I'm planning on removing all the clothes in my hotel so I can carry the backpack around the city. I want to be able to carry basic stuff like a water bottle, extra phone batteries, a small tablet, etc but still have room for any kind of souvenirs I buy. I also don't really want to look like too much of a tourist there.
I'm having a hard time finding one that's big enough to bring clothes to the city but still small enough to walk around all day with. Anyone have any suggestions?