Oh she/he is cute! From my experience and readings, males get more pronounced neon lines coming out from their eyes, whilst females dont have them. Also, males have a dark spot around their anus.
This is the only pic I have of my male where you can sort of see his lines, Ill try to take some clearer pics for you. When you look at him in person they are really noticeable.
Circled are the neon lines and the anal area that is meant to be darker than a females.
But as you suggested, it takes awhile for the markings to become noticeable. Yours still looks quite young, so Id estimate a couple of months before you'll be able to have a better guess.
BTW, I love the 2nd pic- she/he looks so insecure its cute!
Hope this helps,
Bonnie