Since i came out to my dad ive been a bit hopeful for getting hrt before i turn over to age 15. But how likely will they say im too young? Im right now 14 years 7 months (hope to get hrt at or before 15) im 5 foot 3 (still growing) and 114 lbs. My moms bra size is 39B what can i expect for myself? Will i get a possible hourglass figure?

At 14 you would probably look totally cis female
Hour glass depends on your genetics? Whats the girls in your family like? That is in general what you will look like.

I understand that teenagers don't get a full HRT, but delay puberty so your androgynous body doesn't mutate into a fully developed male body. You have great chances of looking completely like a cis woman.

It depends where you live, but most places let you get hormone blockers, which help a lot for mtf puberty since testosterone's effects are a lot more difficult to reverse than estrogen's. I'm 15 and I just started hormones so I know in some states you can get hrt from 13 I think. If it's just a matter of being allowed hormones legally, you can look up local legal requirements online. It very much depends on genetics on how you will grow when on hormones, so look at the women in your family.