Actually, if you go on the internet to sites geared for teen girls and lookup information on these lumps, you'd get the same info you got. Irregular breasts tissue at puberty is very frequent and its never cancer.
I always wonder why TS don't look up info on the internet more often. If your going through puberty, go to sites for those geared towards those going through puberty. These girls are not in your age group (probably, except from some lucky TS) but they are living some of the same body issues.