Freedom of speech is not freedom from criticism.
This is the text of the First Amendment:
Congress shall make no law respecting an establishment of religion, or prohibiting the free exercise thereof; or abridging the freedom of speech, or of the press; or the right of the people peaceably to assemble, and to petition the Government for a redress of grievances.
That is a restriction on the power of government. It doesn't say that you can express yourself in anyway without fear of any repercussions from anyone. It simply says that the government does not have the power to restrict your freedom of expression. The courts have allowed for reasonable exemptions such as laws prohibiting screaming fire in a theater.
Freedom of the Press works the same way. The government does not have the power to censor the press. The courts have since allowed for reasonable exemptions related to National Security. However, just because the government cannot censor the press, that does not mean that a reporter cannot be fired for writing something the paper they work for prohibits them from doing. Similarly, though the government cannot censor you, your employer can certainly fire you for something you say. For example, you are free to say the N word. The government will not penalize you or censor you in anyway for doing so. However, if you use the N word at work or at a company function, you are probably going to get fired. Would that mean your freedom of speech was violated? Of course not. The same is true in this case.
"You're the only person that decides how far you'll go and what you're capable of." - Ben Saunders (Explorer and Endurance Athlete)