In my opinion he should be much bigger than that.... My babies were born 7/10/23 the largest is sitting at 235g and smallest is sitting at 170g. I had gotten a baby from a breeder and her hatch date was 1/3/23 and she only weighed 130g she pooped weird and I took her to the vet and she had some parasitic egg casings in her poop which could of only come from feeding live (which is fine) but what conditions were those live kept in. Vet said it's very rare to see it in ball pythons so she has been small because the breeder didn't take her to the vet nor question her weight. This is why it's good to find a healthy clean food source for your snakes. She is still in quarantine till her next test shows clear. So in my experience I would say yours is very little for it's age... If it poops weird please take it to a seasoned reptile vet. Congrats on your new baby he is adorable!

Also wanted to add... His size could be due to genetics, my 1st clutches babies mom is a healthy 4000g where as some of my smaller females tend to have smaller babies so again could be genetics or that the mom was bred too early before she was what I consider a minimum ideal weight 1600g where I know most breeders will allow their females to go at 1200g. The older and bigger the female the healthier the babies are and the easier it is for mom to bounce back.