Hi!
I bred my BDs a while back and ran into quite a few issues with the babies, and very similar to yours, so I'm happy to help in any way I can.
Okay first off a few different angles of just the tail and then the whole body in good light would be great! and it's eyes too, it's eyes look swollen. Does it have thick goop or anything in the eyes? The tail has tail rot, which isn't good.. for that pure RAW honey will help and saline rinse too. Warm water baths too. That's at lest what I did for the babies I raised... The tail will most likely fall off.
Is the baby shedding? Is that what I'm seeing too?
What is this baby's set up? Light's, how long are the lights on, color of the lights, bedding, stuff in the tank, temps, etc?
As well maybe a humidity box inside it's tank, is it dry where you are at? This may or may not help.. But the other things I said above should.
When it first hatched was it like this?
Does it wheeze or anything like that? Popping noise?
If possible keep this little one separate from the others.
I am also going to recommend a reptile vet for this baby, if possible, she/he looks very uncomfortable, poor thing. I hope for the best for you and your little BD!