My daughters diagnosis took 7 months for her bone cancer (Ewings Sarcoma) By the grace of God, it hadnt spread yet that they could tell at all and she has been in remission for 2 1/2 years. If I were you, I would go to get another opinion. If you feel there might be something out of whack, then getting another opinion would be the right step. Blessings to you and let me know if we can help out more.
Carol