From wikipedia : On Pubertal effects of testosterone
Pubertal effects begin to occur when androgen has been higher than normal adult female levels for months or years. In males, these are usual late pubertal effects. The effects include:[19][20] Growth of spermatogenic tissue in testicles, male fertility, penis enlargement, increased libido and frequency of erection or clitoral engorgement. Growth of jaw, brow, chin, nose, and remodeling of facial bone contours.
I cant stress this enough, if you are incel and still a teenager. Buy some test and inject otherwise you will be incel for life.