"we have a 5 week old baby and he's mostly fine except every night he just freaks out and cries for an hour at 7 pm. one of us has to walk him around the apartment to get him to calm down. wtf??? is this normal?? what are we doing wrong??"
You're not doing anything wrong! In fact, it sounds like you're great parents, because you've figured out your kid's pattern. The first step to fixing a problem is identifying it.
The problem or good part of this situation, depending on how you see it, is that many (I might even go so far as to say a majority) of babies have some kind of regular freak-out in the evening for a few weeks or months. So there is no real fix here except waiting it out.
I've heard it called "the witching hour" in a lot of places, because it just comes with no real reason. You're feeding the child the same food all day, so there's no digestive reason 7 pm should be worse than any other time. At that age they're pretty much still sleeping in short bursts around the clock, so it shouldn't be any particular kind of tiredness.
It seems to be worse from 6-8 weeks, and then fade out until it disappears sometime around 14 weeks. (Your mileage may vary. If you have a kid who kept crying for a really long time, or if you have a kid who had/has actual colic, don't hate me for saying this. You got dealt a crappy hand.) Then, of course, it reappears as soon as you have children of your own and just want to get far, far away during the dinner-bath-bedtime gauntlet every day*.
Many people think the 6-8 weeks thing is because there's a particular spurt of digestive development around that age. A friend of mine is a post-partum doula, and she says every client she has goes through some kind of feeding or digestive thing around 6 weeks, so she just thinks it's universal, and something to be managed, not worried about.
Basically, though, if you can get your baby to calm down, whether by walking your baby around the apartment, using a swing, driving your baby around in a car, turning on a hardryer, wearing the baby in a front carrier and bouncing slowly and deeply around for an hour (my calves looked awesome!), things are OK. Not fun (nooooo, not fun) but OK. This, too, will pass. And you'll be able to tell the story of whatever ridiculous thing you had to do for a few weeks to get your kid to stop wigging out as a newborn.
A note about crying, though: Some kids just need to cry. For whatever reason, they're feeling anger or frustration or some other emotion that makes them want to cry. That's OK. But it's so much nicer to be held while you cry, especially if you're used to being snuggled inside another human being recently. So definitely hold your baby during the fussy times, but don't feel hopeless or bad if your baby keeps crying. Holding your baby teaches them that everything's OK, even when they're feeling crappy enough to need to keep crying.
Does anyone remember this? I've already shared that I had to bounce around for hours wearing my first son (who by 5 weeks was 11 pounds) in a front carrier. How did you survive this phase?
* You guys know I have a seemingly infinite number of Million Dollar Ideas, including such favorites as the Monkey Assistant Training Ranch and Preschooler Boarding School. I have another one, which is that you all elect me Benevolent Dictator (of, I guess, the world), and I institute a policy of Universal Babysitters from 6-9 am and 6-9 pm every day. Think about it: If someone else could get your kids up, dressed, fed, and ready for the day, and then get them fed, undressed, and in bed for the night, the rest of the day would be a relative piece of cake.