For my my BP has gone through growth spurts, 100 to almost 200 grams between months sometimes, and he's a banana morph. I specify this because male bananas tend to be significantly less expensive than females due to how the gene's genetics work (for the sake of simplicity female bananas are harder to produce). He's just over a year old and over 500 grams last I weighed him so he's just a few months behind yours for reference.

So either the breeder somehow did a flub and I got a female for a cheaper price (which is doubtful because he came from a big name professional breeding facility, Dynasty Reptiles), or he's well and truly a male.