My friend hit his head badly!?

i hab this fwend(which im not ganna say der name cuz its personal) well wen he was in da 6thgrade he was on this wall which was a few feet tall n he fell on his back n hit his head on da cement and he got knocked out. later on he felt sick and he vometed and wen he was done vomoting, he pucked somethang black(wierd!) and after the accident he sometimes has black outs(which is rarley) and he culd membaz stuff but somtimes he forgetz but he mostly membaz..i told him to tell his mom to take him to da doctor so da docter culd check on him to see if he has any infection or sumthang!!!!his mom tells him that she will take him to docter but she neva does!!!do u think he has somthing in his brain dat got damaged?plz this worries meh!!!!thx...hes now 15years old =]