LO is 9 weeks today and his longest stretch of sleep is 2-2.5h

He usually sleeps two such stretches and then wakes up every 30min-1h. I feed him if it's more than 2h since his last feeding at night. He is usually in bed by 8pm, I nurse him to sleep for now and swaddle him as well. Since he was 5 days old he sleeps in the crib in his room as he hated the Pack n Play in our bedroom. He actually used to sleep 3h stretches at first, but has regressed in the past couple of weeks

Lately I've been putting him in the swing (stationary) for the second half of the night just because he can sleep a bit longer in there. For naps he either sleeps in the moving swing, in the car seat on stroller rides, or on me. If I put him in the crib he wakes up after 30 min, only movement seems to help him nap longer.
Is there anything that strikes you as wrong/odd and which can be tweaked to improve his sleep at night? He's capable of longer stretches, at 5 weeks he slept once 6h, once 5h and once 4h. I thought he's up to something, but that was it
Re: Sleep - what am I doing wrong?
From what I've read and in my experience, it takes three days to break a habit... Not going to lie - that first day/night can be pretty awful. But it gets better!
One thought based on what helped with our LO's and sleep issues: For overnight wakings, try having someone else soothe baby without taking them out of the crib (shhh noises, patting, and a hand on the back/chest, etc). By not picking them up, they get less woken and also, by having someone else do it, they don't smell you and are less likely to associate the need to feed.
Also, if he's a pacifier baby, try giving him the paci (don't pick him up). If you have someone else there to do it, all the better.
I'd also suggest cutting the swing... It isn't a lasting option and also isn't super safe.
Hope you find a fix -- and some sleep-- soon!
Regarding the swing, in the second half of the night, if I put him on the back in the crib he would wake himself up by pulling his legs up because of gas & reflux, and I found that the recline of the swing helps. But I agree that it's not a good long-term solution...
Please know you aren't doing anything wrong! Sleep is so unpredictable and you sortof just have to go with it until they are a little older.
The idea with pajamas is interesting. LO has always been sleeping in an onesie, socks and the halo swaddle. I'm just afraid he'll overheat though, he's a hot baby
Also thank you to @ElleMF728 for your post...literally breathed a sigh of relief after reading it!