Over An Hour On The Breast?

Is feeding for over an hour at the breast normal for a 3 week old? Baby feeds for 45 minutes on one side and finishes off on the other then 45 minutes to an hour later she's ready again. She chokes a lot and also pops off from my strong letdowns, but my milk also flows so fast that she can't keep up and we both get covered in milk. I feel like an hour is a lot, but she gets so mad when I stop feeding her any earlier. I know pumping isn't really a tell of how much milk she's getting, but when I pump (sometimes I just need a break) I'm getting 4-6 oz in only 15-20 minutes.