Don’t worry about those first set - they yellow & fall off anyway.
The rest look fine - have you used nutes or as tiltswitch....(that name might put me on a terrorist watch list lol) mentioned it could be the medium....
If there’s feed premixed in the medium it might be a little strong. I’d go with coco, perlite & a little munched up seaweed to a rough ratio of 5:1:1 for seedlings until they’re 2 weeks. Then I’d add a little nutes.
If you’re using nutes, use smaller amounts yet. If you aren’t, they might need a little N.