Im 13 and im so short im 4"11 and everyone thinks im a 6th grader im so skinny idk why i eat good but i guess i have a fast digestive system idk and i have a little bit of pubic hair only one is curly and everyone thinks im smart cuz i have glasses and braces BUT IM NOT my grades are bearly good i literally get straight C's literally the 7th and 6th graders are taller than me and why do i have a bump on my nipple first it was the left one then it went back to normal but when it did the right one got a bump amd my penis got The wierd thingy on the top but it hasn't grown yet and it has white bumps all over it
Bumps on your nipples are common for a male during early puberty.
You do sound like you are starting to develop, the pubic hair is one sign. If you can ejaculate then you are in puberty.
What "weird thingy" are your referring to? White bumps can be pearly penile papules or fordyce spots. Google them.