Why doesnt he text me if he asked for my number?

so im pretty sure that the guy i like likes me as well but im not to sure where to go from here... he is my brothers friend and i told my brother about a year ago that i liked this guy but i dont know if he told him or not. lately this guy has been giving me more and more signals like sitting next to me, starting conversations, asking my brother to bring me along, and about six months ago asking for my number. the problem is; why wont he ever text me or anything? am i not good enough or something and if thats it whyd he ask for it in the first place? do i dare send a few signals his way at the risk of embarassing myself? i have thought about flirting with him but am too afraid of rejection and dont know what to say if i text him out of the blue.... can anybody help me out here? im afraid maybe im reading into it too much or something embarassing like that.