Had CT of pelvis &abdomen- doc said all nml- report says mild enlarged spleen 13cm. She said she isn't concerned - CMP, - nml - is 13cm bad?

Mild Splenomegaly. Top normal linear measurement is 9.8 cm: http://www.ajronline.org/doi/abs/10.2214/ajr.184.5.01841510 3 dimensional measurement is more accurate, but 13 is likely a little juicy. Clinical importance is unclear and a medical work up seems advised, but may be unrewarding as this is non specific. If this were me, I'd follow it with serial U/S (maybe repeat in 2-3 mos.) so you don't worry.
Not necessarily. Normal length of spleen on CT is up to 10 cm. A mildly enlarged spleen may or may not be significant. Are you having any signs or symptoms of illness? Why was CT performed? Is your spleen palpably enlarged? Have you traveled overseas? If routine lab studies are normal and you are otherwise healthy and asymptomatic your Dr is likely correct.